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Police investigators work at a blast site outside a building used by court officials in central Makhachkala, Russia, on Monday. At least eight people were killed and more than a dozen injured in twin car-bomb blasts.

MAKHACHKALA, Russia - Two car bombs killed at least two people on Monday in Dagestan, a turbulent province in Russia's North Caucasus region where armed groups are waging an Islamist insurgency. 

Car bombs, suicide bombings and firefights are common in Dagestan, at the centre of an insurgency rooted in two post-Soviet wars against separatist rebels in neighbouring Chechnya. 

Investigators initially said eight people had been killed by the successive blasts in the provincial capital Makhachkala, but law enforcement officials later put the death toll at two and said more than 20 people had been wounded.

Both explosions were near the headquarters of the court bailiffs' service and appeared to have been detonated by remote control, said the federal Investigative Committee, a Russian state agency.

Twisted wreckage of a car could be seen near the building, which was cordoned off by police.

The main suspect in the Boston Marathon bombings in the United States, Tamerlan Tsarnaev, lived in Dagestan with his family about a decade ago and visited the region last year.

The visit by Tsarnaev, who was shot dead by U.S. police after the April 15 bombings that killed three people and wounded 264 others, is being scrutinised by U.S. investigators for signs of ties with insurgents.

Russian President Vladimir Putin has ordered law enforcement authorities to ensure insurgents do not attack the 2014 Winter Olympics next February in the Black Sea resort city of Sochi, which is close to the North Caucasus.

Most of the wounded and the two dead were caught by the second of Monday's explosions, a few minutes after the first, the investigators said.

Insurgents in the North Caucasus have often sought to increase casualties by setting off an initial blast to attract law enforcement officers and then detonating a second bomb.

Dagestan, an ethnically mixed, mostly Muslim region between Chechnya and the Caspian Sea, has become the most violent province in the North Caucasus, where insurgents say they are fighting to carve out an Islamic state out of southern Russia.

At least 405 people were killed in Dagestan in violence linked to the insurgency last year, according to the Caucasian Knot website, which tracks developments in the region.

Putin launched the second war in Chechnya as prime minister in 1999 and likes to take credit for preventing the region from splitting from Russia. But his 13 years in power have been marred by deadly attacks claimed by or blamed on the insurgents.

Related: 

• Makhachkala: Dusty Russian city where Boston suspect felt he 'belonged'
• Video: Former Ambassador: We need to focus on the terrorist groups functioning in Dagestan
• Boston bombing suspects' father 'a good man,' neighbors in Dagestan say

This story was originally published on Mon May 20, 2013 9:06 AM EDT

2013 Getty Images

A view of Makhachkala, where suspected Boston bomber Tamerlan Tsarnaev spent time, on April 25.

MAKHACHKALA, Russia — This dusty capital of Dagestan, Russia’s southernmost republic in the North Caucasus region, was home briefly last year to one of the Boston Marathon bombing suspects.

Tamerlan Tsarnaev, the 26-year-old alleged mastermind behind the Boston attacks, spent six months in the Russian Federation in 2012. At least half of that time he was in Dagestan, visiting his father Aznor Tsarnaev, who had moved back from the U.S. a year earlier. Investigators are trying to retrace the younger Tsarnaev’s footsteps and determine whether he met any Islamic militants during his stay.

His father maintains his son's innocence and said he only met relatives while he was there. He said his son was so taken with the place that he began talking about moving to Dagestan. In an interview with NBC News earlier this week, Aznor said his son "felt he belonged" there.

Adrienne Mong / NBC News

The beach in Makhachkala, Russia, the port city in Dagestan Tsarnaev spent several months in 2012. Its economy is growing rapidly and corruption is rife.

Tough town
A port city that dots the western edge of the Caspian Sea, Makhachkala is surrounded by low-lying mountains on its other sides. (Dagestan means “land of mountains.”)

The beaches reflect none of the glossy luster of Black Sea resorts; speed bumps seem to outnumber traffic lights; Residents and hotel guests complain about long periods of water shortages.

Nonetheless, the capital is enjoying robust economic growth. Construction sites are everywhere and new hotels are being built. Shops are full of well-known western brands, including Apple’s iPhones. Cafés are teeming with young people and families.

But life is not easy in this North Caucasus town. Take the mayor, for instance.

Said Amirov has survived 15 assassination attempts since the 1990s; one of them put him in a wheelchair. He refuses to be photographed in it, wanting to project an image of power and authority in a culture obsessed with male athleticism and physical prowess (wrestling and soccer are the most popular sports).

Though named the Best Mayor of Russia 2012, Amirov is an emblem of corruption, according to one local journalist. When asked about corruption during a press briefing this week about the Boston bombing suspects, Amirov dismissed the topic: “Corruption exists everywhere.”

However, local residents say corruption is particularly rampant in Dagestan.

“If you have money, you can get anything done,” said a former policeman, who quit his job because he couldn’t stomach the corruption in the local police force.

In a town that features a clothing shop called “Tony Montana” – named after the Cuban gangster played by Al Pacino in “Scarface” – men swagger in leather jackets and sweatpants. Police checkpoints dot the main roads and semiautomatic weapons are on plentiful display.

The majority of women wear hijabs and long skirts, but it’s not unusual to see women with uncovered hair, three-inch Louboutin heels and tiny skirts.

With a population of half a million, the capital is also a cultural crossroads. Dagestan is Russia’s most ethnically diverse republic with more than 30 ethnic groups.

Sectarian strife
Apart from geography, Islam is the other tie that binds so many diverse groups. Arab conquerors introduced the religion to Dagestan in the seventh century, making it the oldest Islamic republic in the Russian Federation. Dagestan has between 1,800 to 2,000 mosques, according to official Russian government reports, more than neighboring Chechnya or Ingushetia.

During Friday prayers, hundreds of men streamed toward the white multidomed Central Mosque, the largest in Makhachkala. As they prayed, heavily armed men – some dressed in camouflage, some in civilian clothes – ringed the edge of the mosque grounds.

It is the perfect snapshot of the strife surrounding Islam in Dagestan.

Adrienne Mong / NBC News

The Central Mosque in Makhachkala. Dagestan is the oldest Islamic republic in Russia.

In 1999, Chechen rebels invaded, marking the beginning of the second Chechen war. The arrival of Chechen fighters in Dagestan deepened sectarian rifts between Sufis (those who mix Islam with local customs) and Salafis (ultra-conservative Sunni Muslims who believe they are practicing a “pure” form of Islam and adhere strictly to Shariah law).

As terrorist attacks spread throughout Dagestan – now considered more volatile than Chechnya – Russia’s security forces have cracked down further on dissidents and suspected militants, fueling violence, tension and fear.

“As soon as we began preaching Salafism, the government began targeting us,” said Gadzhi Mohamed, who helps run a local Islamic civil rights organization called “Akhlusuna.” In fact, “as soon as someone says ‘pure Islam,’ they become an enemy of the people, created by the state.”

Related links:

• 'America took my kids away': Mother of Boston suspects insists sons not responsible
• Boston bomb suspect's new home has motley cast of alums
• Source: Bombing suspect showed no fear or remorse during hearing
• NBC News complete coverage of the Boston Marathon Tragedy

Reuters TV / Reuters

Anzor Tsarnaev gives an interview in Makhachkala, April 19, 2013.

MAKHACHKALA, DAGESTAN – In the year and a half that Anzar Tsarnaev has lived on Oleg Koshevoi Street, the father of the two Boston marathon bombing suspects has made a positive impression on some of his neighbors.

"Anzar has always helped me," said Raisa Gorbacheva. The 50-year old cleaning lady is a single mother holding down two jobs in the Dagestani capital.

"He has given me advice," she said, for house repairs and renovations.

"I don't believe it's possible that his sons could have been responsible" for the marathon bombings, she continued. "Because the father is such a good man."

But Gorbacheva said she never met the sons, definitely not the 26-year-old Tamerlan who is believed to have spent six months last year visiting his father.

"I never saw him here," she said.

Another neighbor who did not identify himself also said he had never seen Tamerlan either, but regularly saw the father, one of several thousand Chechens living in the Dagestani capital.

Outside the apartment block where Anzar Tsarnaev keeps a home, there is also an empty shop space that the father is trying to sell. A large red banner advertising its sale with his cell phone number decorates the front of the shuttered store.

Neighbors also said Tsarnaev paid for and built an orange and yellow brick pavement outside the shop.

"Everybody says Dagestan this, Dagestan that," said Gorbacheva. "But this is a place of good people, neighbors who help each other."

Dagestan is Russia's southernmost republic, some 1,200 miles away from Moscow, and situated in the Northern Caucasus.

With a population of under three million, it's predominantly Muslim. In fact, Dagestan is considered the oldest, largest and most ethnically diverse Islamic republic within the Russian Federation.

Despite a troubled historical relationship with Moscow – Dagestanis have resisted Russian rule for three centuries – the republic is considered a supporter of the Russian government. This is in stark contrast to its neighbors like Ingushetia or Chechnya, which fought two wars against the Russians in the 1990s.

But in recent years Chechen militants have crossed over the porous border to bring their violent separatist campaign to Dagestan.

Analysts say the spillover of militant extremists and the attempt to forge a pan-Muslim union across the North Caucasus has provoked a heavy-handed response from Russia. 

It hasn't stopped cities like Makhachkala from becoming more Islamic. Local residents say more women have begun wearing the hijab to cover their head and sometimes their face. And journalists visiting the region say they have noticed the number of mosques has risen quickly in just the past couple of years.

But people who know the Tsarnaevs say the family was not part of the trend toward Islamization. 

"They don't seem too religious," said Gorbacheva, the neighbor. "They didn't have long beards. They were like ordinary Muslims."

A cousin of Zubeidat Tsarnaev – the suspects' mother who is originally from Dagestan – said of the family, "They didn't even pray."

"I have doubts about what really happened in Boston," said Abdurashid Patakhov, the cousin and a former policeman.  "It's impossible to believe."

Patakhov said his cousin's family had endured a very difficult life.

"They were an exiled family," he said, describing Aznar's move from Chechnya to Kyrgyzstan to Dagestan during the sons' young lives.  "He [the father] wanted a better life for the children. That's why he went to the United States."

"But the horns of a devil grow everywhere," he added.

Meanwhile, On Sunday, the "Mujahideen of the Caucasus Emirate's Province of Dagestan" put out a statement distancing themselves from the the actions the Tsarnaev brothers are accused of, saying, "the Caucasian Mujahideen are not fighting against the United States of America. We are at war with Russia, which is not only responsible for the occupation of the Caucasus, but also for heinous crimes against Muslims."

The statement continued, "also, remember that even in respect to the enemy state of Russia, which is fighting the Caucasus Emirate, there is an order by the Emir Dokku Umarov, which prohibits strikes on civilian targets."

Related:

• Bombing suspects: Brothers with foreign roots, American lives
• Chechen insurgents deny any link to marathon bombing
• "We got him!': Boston bombing suspect captured alive

Maria Turchenkova / Reuters

A woman walks along a road in the settlement of Akhty in southern Dagestan, July 4, 2012. All photos made available to NBC News on August 31, 2012.

Maria Turchenkova / Reuters

Salafi preacher Abdurakhim Magomedov gives an interview at his house in the village of Novosasitli, July 13, 2012. Magomedov, a charismatic Salafi preacher whose video sermons are popular on the Internet, says that while Dagestan is not yet ready for jihad, its Muslim population must not live under secular law and Russian rule.

Reuters reports — Little girls in hijabs peek out of tin-roof houses and boys play at "cops and insurgents" in the narrow dirt streets.

At one end of the village of Gimry men are building a new, red-brick madrassa, one of many religious schools springing up across Dagestan, a region in the high Caucasus mountains on Russia's southern fringe, in the throes of an Islamic revival.

More than a dozen young men from the village have "gone to the forest" - the local euphemism for joining insurgents in their hideouts, says village administrator Aliaskhab Magomedov.

"It's a full-fledged jihad," he said. "They don't recognize my authority." Read the full story.

Maria Turchenkova / Reuters

Young men and boys pose for a picture in a street in the village of Gimry, July 9, 2012.

Maria Turchenkova / Reuters

Men build a new madrassa, a religious school, in the village of Gimry, July 9, 2012.

Maria Turchenkova / Reuters

Young Salafi women spend time at a public women's beach in downtown Makhachkala, Dagestan's capital, July 8, 2012. "Five years ago, there were no Islamic clothing shops. Now every other girl wears a hijab," said Fatima Ramzanova, 19, feet curled under her on the sand of a new women-only beach in a full, black Islamic dress she wears against her mother's wishes.

Maria Turchenkova / Reuters

A local resident shows her house, which was seriously damaged during a special antiterrorist operation conducted by the Russian military forces in a building nearby, in the town of Kaspiysk, July 10, 2012.

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