Taliban claim responsibility for Kabul attack

A gunman killed three U.S. contractors and wounded a fourth Thursday evening at the Kabul airport in Afghanistan, Pentagon officials said.

A local Afghan was also killed in the attack at about 6:40 p.m. on the military side of the airport, said U.S. Army Col. Brian Tribus, a spokesman for the NATO-led Resolute Support mission. An Afghan air force official told Reuters the shooter was an Afghan soldier.

Tribus would not confirm whether the dead Afghan was the gunman or a member of the security forces. He provided no information about the victims or their duties.

"This incident is under investigation," he said. "Further information will be released as available and appropriate."

The Taliban subsequently claimed responsibility for the attack.

The unnamed Afghan officer described the Americans as "advisers" and said "no one else was there to tell us the reason" for the attack.

In the past several years, more than 142 members of the U.S.-led coalition fighting Taliban insurgents have been killed in so-called green-on-blue insider attacks by Afghan security forces.

The shooting was apparently the first of its kind since U.S. and NATO forces ceased their combat mission a month ago.

In August, an Afghan solider killed Army Maj. Gen. Harold J. Greene, who was overseeing preparations for the transition. Greene was the highest-ranking U.S. officer to die in combat since 1970