PESHAWAR, Pakistan - A suicide car-bomber blew himself up at a security post in northwest Pakistan on Wednesday, killing nine policemen and three civilians, police said.

The bomber set off his explosives as he pulled up at a police post in Charsadda, a town near the main northwesten city of Peshawar, said senior town police officer Riaz Mohammad.

They tried to stop him but he blew himself up, he said.

There was no claim of responsibility but Pakistani Taliban militants, allied with al Qaeda and based in pockets of lawless territory on the Afghan border, have carried out numerous such attacks over the past two years.

Surging violence across Pakistan and the spread of Taliban influence through the northwest are raising fears about the stability of nuclear-armed Pakistan, an important U.S. ally and vital to efforts to stabilize neighboring Afghanistan.

Terrorism Pakistan