Khalid Mohammed / AP

Security forces inspect the scene of a car bombing on Sadoun Street in Baghdad on Monday. A wave of attacks killed at least 57 people and wounded 168, officials said.

More than 70 people were killed in a wave of bombings in markets in Shi'ite neighborhoods across Baghdad on Monday in worsening sectarian violence in Iraq. 

No group claimed responsibility for the blasts. But Sunni Muslim Islamist insurgents and al-Qaeda' s Iraqi wing have increased attacks since the beginning of the year and often target Shi'ite districts. 

More than a dozen blasts tore into markets and shopping areas in districts across the Iraqi capital, including twin bombs just several hundred meters apart that killed at least 13 people in the capital's Sadr City area, police and hospital officials said. 

"A driver hit another car and left pretending to bring traffic police. Another car rushed to take him away and right after his car exploded among people who had gathered to see what was happening," said bystander Hassan Kadhim. "People were shouting for help and blood covered their faces." 

Tensions between the Shi'ite leadership and the Sunni Muslim minority are at their worst since U.S. troops left in December 2011, and the conflict in Syria is straining Iraq's fragile communal balance. 

More than 700 people were killed in attacks in April, according to a U.N. count, the highest monthly toll in almost five years. So far in May more than 300 have died. 

Thousands of Sunnis began staging street protests last December against Shi'ite Prime Minister Nuri al-Maliki, whom they accuse of marginalizing their sect since the fall of Saddam Hussein after the 2003 invasion. 

The latest surge in violence began in April after a raid by the Iraqi army on a Sunni Muslim protest camp in the town of Hawija led to clashes with the security forces and more attacks. 

Bombings on Shi'ite and Sunni mosques, security forces and Sunni tribal leaders over a month-long surge in violence are heightening worries Iraq risks returning to the level of sectarian violence that killed thousands in 2006-2007. 

Related:

• Explosions in Baghdad kill more than 60
• Suicide bomb kills 27 at Baghdad Internet cafe
• At least 20 dead, 200 hurt in wave of attacks across Iraq

Yazan Homsy / Reuters file

A church in Homs was heavily damaged in fighting, as seen here in December. It is unclear whether the damage was caused by Syrian government or opposition forces.

Armed opposition groups in Syria appear to have looted Christian churches and destroyed a Shiite Muslim mosquee in recent months, New York-based Human Rights Watch said Wednesday.

The rights group said it had previously documented the destruction of a Sunni mosque in Taftanaz by government troops fighting for President Bashar Assad.

The war has already killed more than 60,000 Syrians, according to U.N. estimates.

Human Rights Watch warned an increase in sectarian violence can only make things worse.

"The destruction of religious sites is furthering sectarian fears and compounding the tragedies of the country," Sarah Leah Whitson, Middle East director for Human Rights Watch, said in a statement.

"Leaders on both sides should send a message that those who attack these sites will be held accountable," she added.

Sunni Muslims make up about three-quarters of the population, and most of the rebel fighters are Sunnis, according to the CIA's World Factbook.

Assad, however, is a member of the Alawite sect, which is more closely linked to Shiite Islam. Many of his appointees in high government and the military are also Alawites.

Human Rights Watch noted that international humanitarian law requires warring parties to avoid deliberate targeting or seizure of religious buildings that aren't being used for military purposes.

The group said it found evidence in three villages of attacks against religious sites after opposition groups had taken over and driven out government forces. In each area, religious minorities had fled in large numbers, if not entirely.

Villagers flee
In Zarzour, majority Sunnis told the group that their Shiite neighbors fled because they feared they would be attacked by opposition fighters if there was a perception that they had been supportive of government forces.

The Sunni villagers told Human Rights Watch that the Shiites had given "preferential treatment" to government forces when they were in Zarzour.

The rights group said its observations and witness accounts indicated that opposition fighters deliberately started a fire in a Shiite mosque when it took over the village.

In Jdeideh, local residents told observers that gunmen "operating in the name of the opposition" had broken into and stolen from a Christian church after the area came under rebel control.

Observers from the group said it appeared that gunmen had broken in, stolen from the church and fired numerous shots inside, shattering windows and causing structural damage.

A villager told observers that the fighters had used the adjacent priest's quarters to fire at government forces and had stolen medicine from a clinic owned by the church, looted homes and kidnapped civilians.

The rights group said it could not determine whether there was a religious motive for any looting or kidnapping.

In a third village, Ghasaniyeh, the group found that a local church had been broken into and gasoline and diesel fuel had been stolen. An observer found that the church doors had been forced open and that a cross had been left on the floor, but the group said the building otherwise was undamaged.

"The opposition of Syria should back up its claims that it will uphold minority rights by protecting places of worship," Whitson said in her statement.

Calls and emails to the National Coalition of Syrian Revolution and Opposition Forces and a representative of the Syrian National Council were not immediately returned.

Slideshow: Syria uprising

A look at the violence that has overtaken the country.

Launch slideshow

Related:

Syrian refugees: 'We escaped death'

Activists: Assad forces used 'poisonous gases'

Paula Bronstein / Getty Images

A Rohingya girl carries water to her tent at an IDP (internally displaced peoples) camp on the outskirts of Sittwe, Myanmar, Nov. 24, 2012.

Paula Bronstein, Getty Images — In Myanmar an estimated 111,000 people were displaced by sectarian violence in June and October. The violence affected mostly the ethnic Rohingya people who now live in crowded IDP camps racially segregated from the Rakhine Buddhists in order to maintain stability. Around 89 lives were lost during a week of violence in October, the worst in decades. As of 2012, 800,000 Rohingya live in Myanmar. The Rohingya are one of the most persecuted minorities in the world, according to the United Nations.

EDITOR’S NOTE: Images made available to NBC News on Nov. 27

Kyaw Tin examines a woman named Mumtaz at a government-run medical clinic on the outskirts of Sittwe, Myanmar, Nov. 25. Mumtaz was later taken to a local hospital.

A pregnant woman suffers from labor pains as foreign medical teams try to assist Rohingya in need at a makeshift medical clinic on the outskirts of Sittwe, Myanmar, Nov. 25.

A worker builds new housing aimed at offering the Rohingya an alternative to tented IDP (internally displaced peoples) camps on the outskirts of Sittwe, Myanmar, Nov. 25.

Aaisha sits with her 11-month-old baby Bibi at an IDP (internally displaced persons) camp on the outskirts of Sittwe, Myanmar, Nov. 23.

Rohingya pray inside a makeshift mosque during Friday prayer at an IDP (internally displaced peoples) camp on the outskirts of Sittwe, Myanmar, Nov. 23.

Gulzar looks out from her tent at a crowded IDP (internally displaced peoples) camp on the outskirts of Sittwe, Myanmar, Nov. 25.

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