The DeKalb, Ill., native was one of six soldiers injured by the rocket-propelled grenade, which also killed 2nd Lt. Darryn Andrews, of Dallas, Texas.
All of the soldiers injured or killed in the attack were assigned to Company B, 1st Battalion, 501st Parachute Infantry Regiment, 4th Brigade Combat Team (Airborne), 25th Infantry Division.
Martinek joined the Army in March 2008, arrived in Alaska in September 2008 and deployed to Afghanistan in March 2009, the Department of Defense said. Martinek's realtives have been notified.
