The Marine Corps is mourning the loss two helicopter pilots killed when their AH-1Z Viper crashed Saturday in Arizona, whom the Corps has identified as Maj. Matthew M. Wiegand and Capt. Travis W. Brannon.

The two pilots were conducting a training flight as part of the Weapons and Tactics Instructor Course when their helicopter went down at Marine Corps Air Station Yuma, Arizona, officials said. The cause of the crash is under investigation.

Their deaths are a “tremendous loss,” said Brig. Gen. Roger B. Turner Jr., head of Marine Air Ground Task Force Training Command at Twentynine Palms, California.

“Our thoughts and prayers remain with their families and loved ones during this extremely difficult time,” Turner said in a Marine Corps news release.

Wiegand, 34, joined the Marine Corps in 2008 and was assigned to Marine Aviation Weapons and Tactics Squadron One in Yuma, the news release says.

Originally from Ambler, Pennsylvania, Wiegand had previously deployed to Okinawa as part of the Unit-Deployment program and taken part with several bi-lateral military exercises, the news release says. He was qualified on both the Viper and AH-1W Super Cobra and his military awards include the Navy and Marine Corps Achievement Medal with gold star in lieu of second award.

Brannon, 30, was assigned to Marine Light Attack Helicopter Squadron 367 at Marine Air Corps Station Kaneohe Bay, Hawaii. He was attending the Weapons and Tactics Instructor course at the time of the crash.

The Nashville native had taken part in a Marine rotation to Australia and his decorations include the Global War on Terrorism Service Medal and Sea Service Deployment Ribbon.

“We join the families of Maj. Wiegand and Capt. Brannon in mourning the loss of a loved one,” Col. Kelvin W. Gallman, commander of Marine Aviation Weapons and Tactics Squadron One, said in the news release. “Our most valued assets are the individual Marines and our primary focus is supporting the families during this difficult time.”

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