At least 20 militants were killed when security forces repulsed a terror attack by militants on Salala check-post in Mohmand Agency, media quoting military sources said on Tuesday. According to reports, unidentified militants armed with heavy weaponry attacked Salala check-post late on Monday night erupting clashes between the two sides. “The military retaliated with heavy gunfire, forcing the militants to disappear again into their hide-outs,” sources said. "The clash continued for hours between the two sides,” they said adding that at least 20 militants were killed during the fight while four soldiers were reportedly injured during the incident. Earlier on November 26, Nato forces attacked same post killing at least 24 Pakistani soldiers. The matter is still a bone of contention between US and Pakistan as the Nato supply from Pakistan to Afghanistan was halted soon after the incident and still both sides were negotiating to resolve the matter in a peaceful manner.