At least 25 people killed in Afghanistan suicide blast

At least 26 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 said. It was the latest incident in a series of attacks believed to have orchestrated by the Taliban in a bid to destabilize the country's government as U.S. troops are scaling down their presence.

The attack happened just before 7pm, it was reported, when many people were breaking their Ramadan fast. 

The bombing hit a checkpoint manned by members of the Khost Provincial Force, an Afghan unit that guards Camp Chapman, said Youqib Khan, the deputy police chief in Khost province. It wasn't immediately clear whether the bomber was trying to get onto the base or what led to his attack, Khan said. A U.S. defense official said Chapman is an Afghan base with some American special operations forces.

A local hospital received the bodies of at least 26 Afghan civilians, mostly women and children including eight members of a single family, said Dr. Hedayatullah Hamedi, the province's health director. He said the blast wounded nine civilians.

"The explosion was so loud and strong that almost all of the city of Khost was shaken by the blast," provincial police chief Gen. Faizullah Ghyrat said.

A statement issued by the Khost provincial governor's office offered different casualty numbers, saying that 33 people were killed — 27 civilians, including 12 children, and six members of the Afghan security forces. Another 12 members of the Afghan security forces were injured, according to the statement. The discrepancy in the casualty numbers could not immediately be reconciled.

The suicide bomber carried out his attack when many civilian vehicles were waiting to pass by on a main road, said an Afghan police officer who spoke on condition of anonymity because he wasn't authorized to discuss the attack. He said the civilians killed and wounded in the attack were in vehicles waiting for their turn to pass.

Foreign and Afghan forces blocked journalists and police from accessing the site after the blast. Pentagon officials referred comment to NATO authorities in Afghanistan. In a statement, NATO said "no U.S. or coalition personnel were injured as a result of the attack," without elaborating.

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

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

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

Last month, the armed group launched an attack on Afghanistan's parliament, killing five people and losing another seven of its own members.

The Taliban launched its annual spring offensive in April.

The surge in attacks has taken a heavy toll on civilians, according to the United Nations Assistance Mission to Afghanistan.

In the first four months of 2015, civilian casualties jumped 16 percent from the same period last year, it said.

Al Jazeera and wire services