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Dozens killed in Syrian blast as UN says 60,000 dead in conflict

The United Nations is now raising the death toll in Syria to over 60,000 as fighting in the country continues. NBC's Frances Kuo reports.

Updated at 11:40 a.m. ET: At least 30 civilians were killed Wednesday when Syrian warplanes bombed a gas station in a suburb on the eastern edge of Damascus, opposition campaigners told news agencies, as the United Nations announced that the death toll from the conflict had surpassed 60,000.

"The number of casualties is much higher than we expected and is truly shocking," U.N. Human Rights Commissioner Navi Pillay said, citing an "exhaustive" U.N.-commissioned study into more than a year and a half of fighting in Syria.

Of Wednesday's incident near Damascus, activist Abu Saeed told Reuters: "I counted at least 30 bodies. They were either burnt or dismembered."

Shaam News Network via AP video

This still image taken from video shows a wounded man being pulled from the site of a purported Syrian government airstrike on a gas station in the eastern Damascus suburb of Mleiha on Wednesday.

Another activist, Abu Fouad, said warplanes had bombarded the area as a consignment of fuel arrived and crowds packed the station.

An amateur video posted online showed charred and dismembered bodies and vehicles in flames. The Associated Press reported that the video appeared genuine and was consistent with information it had received.

NBC News has been unable to independently confirm the accounts.

The reported airstrike continued a day of intense violence in the country.

Earlier, rebels in the north attacked a sprawling air base as the opposition expanded its offensive on military airports.

The Britain-based Syrian Observatory for Human Rights said the rebel assault on the Afis military air base near Taftanaz was preceded by heavy shelling of the area, and the fighters appeared to be trying to storm the facility.

Observatory director Rami Abdul-Rahman described the attack as one "of the most intense" on the airfield. There was no immediate account of the fighting around the air base from Syrian state media.

Grim accounting
Wednesday's violence served to underscore the U.N. report on the bloody conflict. Pillay said in Geneva that researchers cross-referencing seven sources over five months of analysis had listed 59,648 people killed in Syria between March 15, 2011, and Nov. 30, 2012.

Opposition activists in Syria say government warplanes bombed a gas station in Damascus as fuel arrived, killing at least 30 people. NBCNews.com's Dara Brown reports.  

"Given that there has been no let-up in the conflict since the end of November, we can assume that more than 60,000 people have been killed by the beginning of 2013," she said.

There was no breakdown by ethnicity or information about whether the dead were rebels, soldiers or civilians. Previously, the Syrian Observatory for Human Rights had put the toll at around 45,000 confirmed dead but said the real number was likely to be much higher.

PhotoBlog: Syrian rebel chief tries to unite militias

Increased attacks on airports
In the past few weeks, Syrian rebels have stepped up their attacks on airports around the neighboring province of Aleppo, trying to chip away at President Bashar Assad's air power, which poses the biggest obstacle to the opposition fighters' advances.

Muhammed Muheisen / AP

A look back at the violence that has overtaken Syria.

As its control of large swaths of territory has slipped over the past year, the government has increasingly relied on its warplanes and helicopters to strike rebel-held areas.

Several past rebel attempts to capture the Taftanaz base have failed.

View from northern Syria: Rebels control countryside

The Observatory said Syrian army helicopters were helping defend the airfield against the rebel assault. It added that four rebels were killed in the clashes around the base and that one helicopter was hit by rebel fire.

The Observatory said the rebels attacking Taftanaz base included members of Jabhat al-Nusra, which has been branded a terrorist organization by the United States and is affiliated with al-Qaida, Ahrar al-Sham Brigade and other units operating in Syria's northwestern province of Idlib. The group's fighters have been among the most effective on the rebel side in their battle to oust Assad.

Aleppo forced to halt flights
On Tuesday, clashes between government troops and rebels forced the international airport in Aleppo to stop all flights in and out of Syria's largest city.

ITV's Emma Murphy spoke with Syrian refugee women in Jordan who described harrowing, brutal treatment.

The rebels have been attacking three other airports in the Aleppo area, including the Mannagh military helicopter base near the Turkish border. They have posted dozens of videos online that appear to show fighters shooting mortars, homemade rockets and sniper rifles at targets inside the bases.

The Local Coordination Committees, another activist group, said rebels Wednesday bombarded the Mannagh air base, which has been subjected to almost daily attacks since late last month. 

Rebels have been fighting for control of Aleppo since launching an offensive on the city over the summer.

The fight over the commercial hub has turned into a bloody stalemate, although rebels have captured large swathes of territory in the surrounding Aleppo province west and north of the city up to the Turkish border.

The Associated Press and Reuters contributed to this report.

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.

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