Two Marine aviators were killed on Saturday when their AH-1Z Viper went down over Yuma, Arizona. They’re now identified as Maj. Matthew M. Wiegand and Capt. Travis W. Brannon.

Their helicopter crashed during routine training operations tied to the semi-annual Weapons and Tactics Instructor Course held in Yuma, hosted by Marine Aviation Weapons and Tactics Squadron One (MAWTS-1). The cause of the crash remains under investigation.

Major Wiegand was assigned to MAWTS-1 and held qualifications to fly both the AH-1Z Viper and AH-1W Super Cobra. Major Wiegand had participated in a number of bi-lateral exercises with joint and foreign partners during a deployment to Okinawa, Japan. His list of personal decorations included the Navy and Marine Corps Achievement Medal with gold star in lieu of a second award.

“It is a somber day for the entire Marine Air Ground Task Force Training Command as we mourn this tremendous loss,” Brig. Gen. Roger B. Turner Jr., the commanding general of Marine Corps Air Ground Task Force 29 Palms, told the press.

Capt. Travis W. Brannon was assigned to Marine Light Attack Helicopter Squadron (HMLA) 367, Marine Aircraft Group 24, 1st Marine Aircraft Wing, Kaneohe Bay, Hawaii. Captain Brannon was attending the Weapons and Tactics Instructor (WTI) course 2-19 on Yuma Air Station. He deployed to Australia as a part of Marine Rotational Force Darwin. Captain Brannon’s personal awards included the Global War on Terrorism Service Medal and a Sea Service Deployment Ribbon.

“We join the families of Maj. Wiegand and Capt. Brannon in mourning the loss of a loved one,” said Col. Kelvin W. Gallman, commanding officer of MAWTS-1. “Our most valued assets are the individual Marines and our primary focus is supporting the families during this difficult time.”

The WTI is a seven-week rotation meant to help train Marines to incorporate Marine Corps’ planning and implementation of advanced air and ground tactics throughout a series of increasingly complex training scenarios. Upon completion of the course, Marines become certified as Weapons and Tactics instructors.

“Weapons and Tactics instructors serve as squadron training officers who use their skills to act as aircraft and weapons subject matter experts to provide their units with proper training and evaluation to ensure exceptional combat readiness,” according to the Marine Corps.

Images of the Captain Brannon and Major Wiegand have not yet been released.