A car bomber blew himself up at a police training centre in Pakistan's northwestern city of Hangu early on Thursday, killing at least seven people.
The attack was the latest in a spate of violence across Pakistan in which nearly 140 people have been killed, mostly soldiers and policemen, since army commandoes stormed a radical mosque in the capital Islamabad last week.
The government says 102 people were killed during the entire operation on the Lal Masjid or Red Mosque complex to crush a militant movement led by rebel clerics.
In the Hangu attack, the bomber tried to get into a police centre early in the morning when young recruits were going in for training.
"The attacker tried to crash through the gate. He blew himself up as security guards at the gate tried to stop him," said Fakhr-e-Alam, top administration official of the city.
"Six policemen and a passerby were killed."
A police official said 13 people were wounded.
Hangu, which itself has a history of sectarian violence, is close to Pakistan's lawless tribal regions on the Afghan border, known as hotbeds of support for al Qaeda and Taliban militants.
A large number of al Qaeda fighters and their allies fled to Pakistan's tribal areas after U.S.-led forces toppled the Taliban regime in Afghanistan in 2001.
At the same time as militants are believed to be taking revenge for the government's mosque complex assault in the capital, pro-Taliban fighters have abandoned a 10-month-old peace pact in North Waziristan, raising fears of a resurgence in violence, mainly in the conservative northwest.