Pathankot, Rabi'I 22, 1437, Jan 2, 2016, SPA -- Suspected militants infiltrated an Indian air force base near the border with Pakistan on Saturday and exchanged fire with security forces for hours, leaving at least four gunmen and two Indian troops dead, officials and news reports said. The attack at the Pathankot air force base began a couple of hours before dawn, and by late morning it appeared that the violence had ended with the killing of the gunmen by Indian forces. But just two hours later, fresh gunfire erupted, with an air force helicopter firing at an area of the base. Shots could also be heard from inside Pathankot, a major air force base located about 430 kilometers (267 miles) north of New Delhi, AP reported. Air force spokeswoman Rochelle D'Silva said Saturday night that troops were conducting combing operations of the entire base in order to be able to fully secure it. She added that the full number of casualties would be clear once the base was completely secured. By 8 p.m., no gunfire had been heard around the base for more than two hours. The defense ministry said there had been intelligence reports about a likely terror attack on military installations in Pathankot, and that the air force had been prepared to thwart any attackers. --SPA 19:40 LOCAL TIME 16:40 GMT www.spa.gov.sa/w