Taliban militants strapped explosives to two men accused of being U.S. spies and blew than up at a public execution in northwest Pakistan, intelligence officials and residents said on Friday. The killings took place on Thursday evening in North Waziristan . Five masked militants paraded the hand-cuffed men before dozens of people in the Datta Kheil area and accused them of passing information to the United States on targets for its CIA-operated pilotless drone aircraft. "They strapped explosives around their bodies and then blew them up," a Pakistani intelligence official in the region told Reuters by telephone. Militants have killed hundreds of people they suspect are spies for the United States or the Pakistani government over the past few years. They usually decapitate or shoot the suspects. Residents said this was the first time the militants had blown up suspected spies.