WASHINGTON — The Pentagon has released the identities of four Texas National Guardsmen killed in a helicopter crash in Iraq.

The Defense Department identifies the dead Texans as 38-year-old Chief Warrant Officer Corry A. Edwards of Kennedale, 37-year-old Sgt. Anthony L. Mason of Springtown, 54-year-old 1st Sgt. Julio C. Ordonez of San Antonio, and 28-year-old 1st Lt. Robert Vallejo II of Richland Hills.

All four were assigned to the 2nd Battalion, 149th Aviation, 36th Combat Aviation Brigade, Texas Army National Guard in Grand Prairie. Also killed were three Oklahoma National Guard members.

The CH-47 Chinook was flying in a four-helicopter formation from Kuwait to the U.S. military base at Balad when it crashed early Thursday about 60 miles west of Basra. Military officials say they suspect a mechanical malfunction.