(Reuters) – Unidentified gunmen attacked a school in Pakistan on Monday and killed a guard, police said, raising fears of a repeat of a deadly school attack five months ago that toughened Pakistan’s resolve to fight militants. Police said all teachers and children at the high school for boys were safe after the gunmen killed the guard in the central town of Dera Ghazi Khan, 500 km (300 miles) southwest of Islamabad. “We are still not sure how many gunmen there were and whether they are still there. The police are searching,” district police officer Rehmat Ullah Khan Niazi told Reuters.