NYC firefighter among 3 U.S. Marines killed in Afghanistan

April 9 (UPI) -- Military officials said Tuesday three U.S. troops killed by a roadside bomb in Afghanistan were all Marines.

The improvised explosive device detonated along a convoy near Bagram Airfield in northeast Afghanistan. Their identities will be disclosed after family members have been notified, but one was a decorated New York City firefighter. He was identified as Marine Corps Staff Sgt. Christopher Slutman by a volunteer brigade he was also part of.

Three other U.S. troops and an Afghan civilian contractor were injured in Monday's blast. Initial reports said the contractor was also killed, but a NATO Resolute spokesman said that person is still alive. Navy Secretary Richard Spencer noted Tuesday that all three dead were members of the Marine Corps.

The Taliban claimed responsibility for the bomb.

Seven U.S. troops have been killed in Afghanistan so far this year. The U.S. military has 14,000 troops in the country to train, advise and assist Afghan forces in their fight against the Taliban. Negotiations are continuing between U.S. officials and the Taliban about an American withdrawal.