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Bomb explodes near hotel used by UN monitors, Syrian state TV reports

Syrian rebels attack the staff headquarters of the Syrian military in Damascus on Wednesday morning. NBC's Ayman Mohyeldin reports.

Updated at 6:20 a.m. ET: A bomb exploded in Damascus on Wednesday near a hotel used by United Nations monitors, Syrian state television reported.

The bomb, which was placed in a parking lot near the Dama Rose Hotel, blew up a fuel truck that sent clouds of black smoke into the sky above the capital. At least three people were reportedly injured.

A witness said the explosion had gone off at around 8.30 a.m. local time  (1:30 a.m. ET) and damaged a building opposite the hotel, but appeared not to have damaged the hotel itself. 

Syria's deputy foreign minister, Faisal Mekdad, said none of the observers had been wounded in the blast, state television said. "This was a criminal act aimed at distorting Syria's image," it quoted him as saying.

Bassem Tellawi / AP

Security officers investigate the scene after a bomb exploded outside a Damascus hotel popular with U.N. observers on Wednesday.

A spokesman for the Free Syrian Army told NBC News' Ayman Mohyeldin that the rebel forces were responsible for the attack, which was targeting military staff headquarters.  Plans for the attacks on a high-level meeting of the chiefs of the different military branches had been in the works for close to a month, the FSA spokesman said.

Photos: Explosion hits near Damascus hotel used by UN

The area is home to a club for army officers and a building belonging to the ruling Baath Party and is also not far from the army command.

The explosion occurred as U.N. humanitarian chief Valerie Amos was in the Syrian capital. However, her team is believed to be staying at a different hotel. 

One of the most senior figures to defect from President Assad government today called the regime "an enemy of God". Former Prime Minister Riad Hijab said the government is losing its grip on the country and is collapsing. ITV's John Ray reports.

Video from the site of Wednesday's explosion broadcast by El-Ikhbariya, a pro-government channel, showed firefighters hosing down a steaming fuel truck whose tank was blasted open near the hotel. A row of white U.N. vehicles parked nearby was covered in ash and dust.

'Violence is increasing'
The bombing follows a statement Monday by the head of the U.N. monitors blaming both forces supporting the government of President Bashar Assad and rebel fighters for ignoring the plight of civilians. 

"It is clear that violence is increasing in many parts of Syria," General Babacar Gaye, head of the U.N. Supervision Mission in Syria, told journalists in Damascus. 

NBC News

People resisting the army of President Bashar al-Assad in northern Syria cope with loss and prepare for fighting.

"The indiscriminate use of heavy weapons by the government and targeted attacks by the opposition in urban centers are inflicting a heavy toll on innocent civilians. 

"I deeply regret that none of the parties has prioritized the needs of civilians." 

Eerie stillness in Aleppo as Syrian rebels pull back

Eighteen months of violence -- including alleged massacres by the regime -- has led to the deaths of more than 20,000, according to activists. 

Iran meddling?
Meanwhile, Defense Secretary Leon Panetta said Iran was building and training a militia to help Assad's regime battle the rebel fighters trying to topple him. 

The Iranian efforts, said Panetta, will only add to the killing going on in the country and "bolster a regime that we think ultimately is going to come down." 

The Syrian Prime Minister, who defected to the rebel side, said that President Bashar Assad's regime is near collapse. NBC's Ayman Mohyeldin discusses.

Iran has accused the United States and its allies of similar intervention in Syria. 

Sitting alongside Panetta at a Pentagon news conference Tuesday, Army Gen. Martin Dempsey, chairman of the Joint Chiefs of Staff, said the militia, which is generally made up of Syrian Shiite forces, is being used to take the pressure off the Syrian regime forces. 

"Any army would be taxed with that kind of pace," Dempsey said. "They are having resupply problems, they are having morale problems, they are having the kind of wear and tear that would come of being in a fight for as long as they have." 

Will world inaction help al-Qaida gain foothold in Syria?

Dempsey also said that it appears Syrian rebels were able to shoot down a Syrian warplane but said he has seen no indication that they are armed with heavy weapons or surface-to-air missiles, at least not yet. 

Opposition forces claim to have shot down a Syrian plane and captured the pilot, but the Assad regime has denied the shooting. NBC's Brian Williams reports.

He says the MiG fighter could have been shot down with small arms fire. Syria has blamed the crash on a technical malfunction, but Dempsey said the cause "didn't appear to be mechanical." 

Dempsey and Panetta voiced concerns about Iran's growing presence in Syria even as Assad's government steps up its aerial attacks against the rebel forces. Fierce fighting and attacks from warplanes and helicopter gunships have pushed the opposition forces back on key fronts, such as Aleppo. 

Goran Tomasevic / Reuters

After months of protests and violent crackdowns, a look back at the violence that has overtaken the country.

Asked about military options for intervention in Syria, Dempsey said the U.S. has been in discussions with Jordan and Turkey about the possible need for a safe zone because the two countries neighboring Syria are seeing an influx of refugees fleeing the fighting. 

US, Turkey explore no-fly zones over Syria

"And with a safe haven would probably come some form of no-fly zone, but we're not planning anything unilaterally," Dempsey said. 

Machine guns operated by motorcycle brakes? Get a glimpse at the rebels fighting against Assad's forces in Syria's mountainous Jabal al-Zawiya area.

Panetta repeated assertions he made during an Associated Press interview Monday, saying that right now, creating a no-fly zone in the region "is not a front-burner issue" for the U.S. Instead, he said, the U.S. is focusing on providing humanitarian and nonlethal assistance and on ensuring the chemical and biological weapons in Syria are secure. 

A no-fly zone would be a militarily enforced area in which outside nations would prohibit Syrian warplanes from flying and attacking Syria's own people. 

Reuters and The Associated Press contributed to this report. 

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