(The Hill) — Five U.S. service members were killed Friday evening after their aircraft suffered a mishap and crashed into the eastern Mediterranean Sea, the Pentagon revealed Sunday. 

The mishap took place “during a routine air refueling mission as part of military training,” and all onboard the aircraft were killed, U.S. European Command (EUCOM) said in a brief statement.  

An earlier release from EUCOM stressed that the aircraft crash “was purely related to training and there are no indications of hostile activity.” 

The command gave no further details on the type of aircraft involved in the crash, the military service it belonged to, or the exact location or timing of the accident. 

Nearby U.S. military aircraft and ships began search-and-rescue efforts immediately, and the incident is under investigation.

“Out of respect for the affected families, and in accordance with Department of Defense policy, the identities of the crewmembers are being withheld until 24 hours after next of kin notifications have been completed,” according to the statement.

“Our thoughts and prayers are with the families of the fallen,” it added. 

The Pentagon has moved additional U.S. forces to the Middle East following the Oct. 7 attack by Hamas militants on Israel. 

The U.S. military deployed the USS Gerald R. Ford strike group to the eastern Mediterranean and the USS Dwight D. Eisenhower strike group to the Persian Gulf. 

President Joe Biden released the following statement:

“Today, Jill and I mourn the loss of five American service members who died when their aircraft crashed in the Mediterranean Sea during a routine training mission. Our service members put their lives on the line for our country every day.  They willingly take risks to keep the American people safe and secure.” President Biden said in a statement. “And their daily bravery and selflessness is an enduring testament to what is best in our nation. Jill and I are praying for the families and friends who have lost a precious loved one—a piece of their soul.”

Secretary of Defense Lloyd J. Austin III issued this statement following the crash:

We mourn the tragic loss of five U.S. service members during a training accident in the Mediterranean Sea early Saturday morning. While we continue to gather more information about this deadly crash, it is another stark reminder that the brave men and women who defend our great nation put their lives on the line each and every day to keep our country safe. They represent the best of America. We will remember their service and their sacrifice. My prayers are with the patriots we have lost today and their families, loved ones, and teammates.