U.S. airstrikes in Yemen killed four al Qaeda militants, including a man suspected of being involved in the 2000 bombing of the USS Cole, Yemeni officials said Tuesday. The officials said missiles struck a school and a car late Monday, and tribal officials said the militants were holding an important meeting at the school. A U.S. security official in Washington confirmed the attacks but would not comment on any of the specifics. Also on Tuesday, the top U.S. intelligence official said that the U.S. has been placing increased pressure on al Qaeda’s leadership in Pakistan, causing the terror cell to break apart into affiliates in North Africa, Iraq, and Yemen. The Yemeni affiliate has so far posed the greatest danger to the U.S., where militants have been able to take advantage of the political chaos.