At least 4 killed in car bomb attack in Pakistan

PESHAWAR, Pakistan, May 5 (Reuters) - A suicide bomber rammed his car into a police checkpoint near the Pakistani city of Peshawar on Tuesday, killing at least four security men, police said.

The attack took place on the border of Peshawar and Khyber, a volatile tribal region bordering Afghanistan.

"The bomber rammed the car into the checkpost. Four security personnel are killed," Peshawar police chief Sifwat Ghayyur told Reuters.

Witnesses, however, said seven people, including five security men and two civilians, were killed. Peshawar is the capital of the North West Frontier Province (NWFP).

Pakistani security forces are battling militants Taliban in a mountainous region of NWFP where militants began expanding their clout after striking a deal with the authorities for imposition of Islamic sharia law.

The February pact and spreading Taliban influence have raised alarm in the United States about the ability of nuclear-armed Pakistan -- important in efforts to stabilise Afghanistan -- to stand up to the militants.

(Reporting by Faris Ali, writing by Zeeshan Haider; Editing by Sanjeev Miglani)