A military helicopter crashed into a school in northern Pakistan Friday, killing two pilots and at least two foreign nationals on board, dpa quoted an army spokesman as saying. Three MI 17 helicopters were flying several Western diplomats to Gilgit-Baltistan region in northern Pakistan where Prime Minister Nawaz Sharif was to address a ceremony, army spokesman Major General Saleem Bajwa said. "Two helicopters landed safely but the third one crashed and caught fire," Bajwa said. The nationalities of the foreign victims were not immediately known.