PESHAWAR: At least three policemen were killed in northwest Pakistan when Islamist militants stormed a district police headquarters in Khyber Pakhtunkhwa province on Monday, a police source told Reuters. The attack on the complex, which houses both the district police headquarters and a residential complex, was ongoing, the high-ranking police source said, adding that the assailants, who included suicide bombers, had been “pinned down” in the area. Three assailants were killed by police, he added.