The Iowa National Guard on Dec. 15 identified the two soldiers killed by a gunman with suspected ties to the Islamic state in Syria.

They are Sgt. William Nathaniel Howard, 29, and Sgt. Edgar Brian Torres-Tovar, 25.

The two sergeants killed were members of an Iowa Army National Guard unit deployed to the Middle East as part of Operation Inherent Resolve, the U.S. military's counter-ISIS mission, the Iowa National Guard said in its announcement.

The soldiers were killed alongside their interpreter in an "ambush by a lone ISIS gunman," U.S. Central Command said in a Dec. 13 statement. "The gunman was engaged and killed."

Three servicemembers were also injured in the attack, according to the statement.