Sanaa : A US drone strike in northeast Yemen has killed four suspected Al-Qaeda members, a tribal source said on Tuesday. Two missiles struck two vehicles late Monday in the Wadi Abida area, east of Sanaa, killing the occupants "who were all Al-Qaeda members," the source said. Obad Mubarak al-Shabwani and Jaafar al-Shabwani, "both local chiefs of Al-Qaeda," were among the passengers, he said.The United States military operates all drones flying over Yemen in support of Sanaa's campaign against Al-Qaeda and has killed dozens of militants in a sharply intensified campaign in the past year.