JALALABAD: A suicide bomber killed two policemen Saturday when he slammed an explosives-laden car into a police headquarters in east Afghanistan, underlining the country's instability as US Secretary of State John Kerry visited Kabul.

Nangarhar provincial spokesman Ahmad Zia Abdulzai said the attack took place Saturday next to the provincial police chief's office in the capital city of Jalalabad.

Abdulzai says the suicide bomber blew up his car at the main entrance of the police compound, destroying the front of the facility. He said one civilian and two officers had been killed.

Gen Masoum Khan Hashimi, Nangarhar's deputy police chief, says the explosion also wounded three civilians and two police officers.

Jalalabad, the capital of Nangarhar province, straddles the main route from Kabul to Pakistan's tribal belt, a hub for Taliban and Al Qaeda-linked militants.

The city has seen a series of attacks in the past year.

In August, suicide bombers targeted the Indian consulate, detonating a car bomb and killing nine civilians, including seven children in a nearby mosque.

There was no immediate claim of responsibility for Saturday's attack, which came as President Hamid Karzai and Kerry held a second day of talks in Kabul.