The U.S. Air Force confirmed Monday that its aircraft had bombed and destroyed a complex of buildings belonging to al-Qaida’s Nusra Front affiliate, bringing to at least three the number of American airstrikes that have targets the terrorist group since bombing in Syria began last year.

The attack came one week after Nusra had defeated an American-backed Syrian rebel group and forced it to disband, capturing an unknown number of U.S.-supplied sophisticated anti-tank missiles.

Local and humanitarian sources said Sunday’s strike killed at least five Nusra militants. A 15-year-old boy, who apparently was working at the site, possibly tending livestock, also was killed, a resident of the nearby Atma camp for displaced Syrians told medical personnel in Turkey. […]