Updated

Afghan police say a truck has exploded on the outskirts of the capital, possibly causing casualties in the first attack in Kabul for almost three weeks.

The head of the criminal investigation division of Kabul police, Farid Afzeli says the truck was packed with explosives and damaged a nearby gas station when it blew up.

He says the vehicle was trying to enter the city but had been stopped by police before it exploded. He says casualties are expected.

NATO confirmed the explosion took place just before 6 a.m. Sunday.

Kabul has been quiet since early January, when a suicide car bomber attacked the headquarters of the European police training mission, killing an Afghan civilian and wounding five others.

Insurgents have intensified the war across Afghanistan in the past year.