Two U.S. Marines killed in a crash in New Mexico during a deployment to the southern border have been identified by authorities.

Lance Cpl. Albert A. Aguilera, 22, of Riverside, California; and Lance Cpl. Marcelino M. Gamino, 28, of Fresno, California, were both killed in the April 15 crash near Santa Teresa, New Mexico. A third Marine, who was not identified, is in critical condition.

“The loss of Lance Cpl. Aguilera and Lance Cpl. Gamino is deeply felt by all of us,” said U.S. Marine Corps Lt. Col. Tyrone A. Barrion. “I extend my heartfelt condolences and prayers to the families of our fallen brothers. Our top priority right now is to ensure that their families, and the Marines affected by their passing, are fully supported during this difficult time.”

The Marines were part of the 1st Combat Engineer Battalion, 1st Marine Division, and were deployed as part of the Joint Task Force-Southern Border operation. Thousands of military personnel have been deployed to the U.S.-Mexico border since President Donald Trump declared an emergency at the border.

The three Marines were airlifted to University Medical Hospital in El Paso on April 15. The crash occurred during a convoy movement along the border, according to a news statement from the Joint Taskforce Southern Border operation. The cause of the crash is still under investigation.

“I am saddened by the loss of two U.S. service members who were killed in yesterday’s accident in Santa Teresa,” U.S. Rep. Veronica Escobar, a Democrat representing El Paso, said. “I’m praying that the third service member who remains in serious condition recovers, and I’m thinking of the families of all involved.”

President Donald Trump declared a national emergency at the southern border in mid-January in response to what he called “an invasion” of cartels and immigrants crossing the border, deploying thousands of active-duty troops.

The first 1,500 troops were deployed to Fort Bliss in El Paso on Jan. 25. There are currently about 6,600 troops along the southern border with Mexico.

The Trump administration is seeking to utilize Fort Bliss as a hub for deportation. Construction of the facility is set to start soon.