At least 33 people have been killed in a suicide car bomb attack near a military base in Afghanistan's Khost province, where Afghan and foreign soldiers are stationed, authorities say.

Al Jazeera's Jennifer Glasse, reporting from Kabul, said that the attack happened just before 7pm, when many people were breaking their Ramadan fast.

"There were a lot of casualities," Glasse said. "Ambulances have been working to get people to hospital."

All of the dead are believed to be Afghan. 

People and Power - Afghanistan: An army prepares

The bomber detonated the explosives at a military roadblock near the entrance to Camp Chapman, Faizullah Ghairat, the Khost city police chief, told the AFP news agency. 

There was no immediate claim of responsibility, but the Taliban has often targeted Afghan and foreign troops.

Foreign troops including US soldiers are stationed at Camp Champan alongside Afghan soldiers.

A statement from the NATO mission in Afghanistan said it was "aware" of the blast, but did not elaborate.

In 2009, Camp Chapman was the target of a spectacular suicide attack claimed by al-Qaeda. Seven CIA officials were killed in the deadliest assault on the US agency since 1983, when eight officers died in an attack on a military base in Beirut.

Camp Chapman is located less than four kilometres from the city of Khost, which is near the Pakistani border, a volatile region where the Taliban and other armed groups hold sway.

Source: Al Jazeera and agencies