DENVER - The Defense Department says Marine Cpl. David M. Sonka of Parker, Colo., has been killed during a combat operation in Afghanistan.

The military said Monday that the 23-year-old Sonka died May 4 in Farah Province along with 39-year-old Marine Staff Sgt. Eric D. Christian of Warwick, N.Y.

Both were assigned to the 2nd Marine Special Operations Battalion at Camp Lejeune, N.C.

Sonka is the second Colorado serviceman killed in two days. Air Force Capt. Mark T. Voss of Colorado Springs was among three crew members killed when a KC-135 aerial refueling tanker crashed on May 3 in Kyrgyzstan.