Authorities say two soldiers who were killed Friday in an Apache helicopter crash at Fort Campbell, Kentucky, have been identified as 37-year-old Chief Warrant Officer 3 Ryan Connolly and 28-year-old Warrant Officer James Casadona.

The crash took place at about 9:50 p.m. Friday, killing the two, who were with the 101st Combat Aviation Brigade, 101st Airborne Division (Air Assault), according to a statement released by the military base. It happened while the crew was conducting routine training.

Connolly, an instructor pilot, joined the Army in 2001 and arrived at Fort Campbell in 2016. Casadona was a pilot who joined the Army in 2012 and arrived at Fort Campbell earlier this year.

“This is a day of sadness for U.S. Army Fort Campbell and the 101st Airborne Division (Air Assault),” Brig. Gen. Todd Royar, acting senior commander of the 101st Airborne Division and Fort Campbell, said. “Our thoughts and prayers are with the families during this difficult time.”

The cause of the crash is still under investigation.

(Photos courtesy of the 101st Airborne Division)