The military announced on Sunday that a helicopter “mishap” during a training exercise on Friday night caused the death of five American service members in the eastern Mediterranean Sea.

The five were Army special operations soldiers, as The New York Times and Washington Post first reported, according to two officials. Officials said that the search and rescue efforts lasted until Saturday before they were terminated.

On Monday, the Department of Defense released the names of the service members: Chief Warrant Officer 3 Stephen R. Dwyer, 38, from Clarksville, Tennessee; Chief Warrant Officer 2 Shane M. Barnes, 34, from Sacramento, California; Staff Sgt. Tanner W. Grone, 26, from Gorham, New Hampshire; Sgt. Andrew P. Southard, 27, from Apache Junction, Arizona; and Sgt. Cade M. Wolfe, 24, from Mankato, Minnesota.

Lt. Gen. Jonathan P. Braga said in a statement, “We mourn the loss of these five incredible soldiers, each of them a national treasure. They come from rare patriotic families with deep military service ties that span multiple generations and formations.”

Officials said that the five belonged to an elite unit, the 160th Special Operations Aviation Regiment (Airborne), also known as the Night Stalkers, based in Ft. Campbell, Kentucky. They were the Army’s best helicopter pilots and often transported Delta Force or Seal Team Six into missions.

The department expressed its condolences to the families of the deceased and said that the incident was being investigated by the U.S. Army’s Combat Readiness Center.

Officials said that the helicopter that crashed was an MH-60 model.

On Saturday, U.S. European Command issued a statement saying that they were looking into the cause of the crash and that there was no evidence of any hostile activity.

The helicopter was on a “routine air refueling mission” when something went wrong, as stated by European Command on Sunday. They did not give any more information about what happened.

A third U.S. official said that the helicopter crashed near Cyprus. The official also said that the crew belonged to special operations forces that were deployed there in case they had to assist in evacuating Americans from the area because of the Israel-Hamas conflict.

• In his statement, Defense Secretary Lloyd Austin said that the crash was a grim reminder of the courage and sacrifice of the men and women who protect our great nation every day. He said that they embody the best of America and that their service and sacrifice will not be forgotten.

Austin said that he was praying for the patriots who died and their families, loved ones, and teammates.

There was some confusion about when the crash happened, as European Command officials and Austin’s statement gave different times, either late Friday or early Saturday. The Pentagon clarified on Sunday afternoon that it was late Friday.

President Joe Biden expressed his grief over the deaths in a statement, saying that military members “risk their lives for our country every day. They take on dangers to keep the American people safe and secure. And their daily heroism and generosity is a lasting tribute to what is best in our nation.”

Biden noted that the crash happened at the beginning of Veterans Day weekend and said, “We once more reaffirm the sacred duty we have to those who serve our nation voluntarily and their families, caregivers, and survivors.”

The president said, “Jill and I are holding the families and friends who have suffered the loss of a dear one-a part of their heart-in our prayers. Their sorrow is felt by our whole nation.”