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PESHAWAR, Pakistan, June 9 (Reuters) - Suspected militants killed four policemen in an ambush near Pakistan's northwestern city of Peshawar on Monday, a police official said.
The militants armed with Kalashnikov assault rifles opened fire on a police van then threw an explosive, setting the vehicle alight, in an attack about 10 km (6 miles) south of Peshawar, the capital of North West Frontier Province.
"Four policemen have been killed in an attack that happened well after midnight," police officer Nasir-ul-Mulk Bangash said.
He suspected it was a revenge attack, after police killed a militant during a clash last week in the nearby town of Nowshera.
Separately, four children were killed in an explosion in the northern town of Chitral late on Sunday. Police said it was investigating the cause of the blast.
Pakistan has seen a wave of militant violence, most of it in the country's northwest and the adjoining lawless tribal belt on the Afghan border and hundreds of people have been killed since the middle of the last year.
The violence had subsided after Pakistan's new government to came to power after defeating allies of President Pervez Musharraf in an election in February, and began peace negotiations with militants.
Although similar pacts the past have failed to curb militancy, the government hopes the tribal leaders can use their influence to rein in militants and stop violence in Pakistan and cross-border infiltration into Afghanistan.
The United States and some of Pakistan's other allies fear deals with militants will free up Taliban and al Qaeda militants, who fled to Pakistan after the fall of Taliban regime in late 2001, to intensify their war against the West in Afghanistan. (Reporting by Faris Ali; Writing by Augustine Anthony; Editing David Fogarty)
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