A suspected U.S. missile strike killed six militants in a tribal region along the Afghan border on Tuesday, Pakistani officials said. Tuesday's strike hit a house in the Ghulam Khan area of North Waziristan. An unmanned drone fired two missiles at the residence, the Pakistani officials said. On Monday, U.S. missiles struck two vehicles in another part of North Waziristan, killing at least 18 alleged militants in two vehicles, they were quoted as saying by the Associated Press.