Maj. Gen. Jeffrey Bannister, a former commander of the 10th Mountain Division who was preparing to retire, died Sunday, the Army announced.

Bannister, 57, was on transition leave in Lake Murray, South Carolina, when he died.

According to medical examiners, Bannister died of natural causes while running around Lake Murray near Lexington, South Carolina, the Army said Wednesday.

He was assigned to U.S. Army Central at Shaw Air Force Base, where he worked as a special projects officer for the Army chief of staff as he awaited retirement in the local area.

“Our thoughts and prayers are with Maj. Gen. Bannister’s family,” said Lt. Gen. Michael Garrett, the commanding general of U.S. Army Central, in a statement. “Our top priority is ensuring the family has all the local support and resources they need during this emotionally difficult time.”

Bannister was survived by his wife, Trese, and their daughter, Lindsey.

Before arriving at Army Central headquarters, Bannister commanded the 10th Mountain Division at Fort Drum, New York, for more than two years. He relinquished command in April 2017.

Bannister had also previously served as the 10th Mountain Division’s deputy commanding general.

“Maj. Gen. Jeffrey Bannister was a legendary soldier and good man who dedicated his life to his family and his country,” said Maj. Gen. Walter Piatt, the current 10th Mountain commander, in a statement. “His wife and daughter are forever a part of the 10th Mountain Division family, and we are grieving with them during this very difficult time.”

From left, Maj. Gen. Walter Piatt, the incoming commander of the 10th Mountain Division, Gen. Robert Abrams, commander of Army Forces Command, and Maj. Gen. Jeffrey Bannister conduct a pass and review during the 10th Mountain Division change of command ceremony on Fort Drum’s Sexton Field on April 27, 2017. (Sgt. James Avery/Army)
From left, Maj. Gen. Walter Piatt, the incoming commander of the 10th Mountain Division, Gen. Robert Abrams, commander of Army Forces Command, and Maj. Gen. Jeffrey Bannister conduct a pass and review during the 10th Mountain Division change of command ceremony on Fort Drum’s Sexton Field on April 27, 2017. (Sgt. James Avery/Army)

Bannister was commissioned through ROTC as an infantry officer after graduating from Campbell University in 1984. He began his 34-year career in 1st Battalion, 504th Parachute Infantry Regiment in the 82nd Airborne Division at Fort Bragg, North Carolina.

He also served in 1st Battalion, 75th Ranger Regiment, and 1st Battalion, 5th Infantry in South Korea. He would go on to command 1st Battalion, 6th Infantry Regiment in the 1st Armored Division, as well as serve as deputy commander of the 75th Ranger Regiment.

In 2005, Bannister took command of 2nd Brigade Combat Team, 2nd Infantry Division, which would later be reflagged as 4th Brigade Combat Team, 4th Infantry Division at Fort Carson, Colorado. He led the brigade into combat in Iraq, on what would be his third deployment in support of Operation Iraqi Freedom.

He went on to serve as the executive officer to the commanding general of Multi-National Forces-Iraq.

Bannister also deployed multiple times to Afghanistan, including as the deputy commander of the 10th Mountain Division and again as the deputy chief of staff for operations for the International Security Assistance Force.

He also served at the Pentagon as the director of strategy, plans and policy for the Army G-3/5/7.

In addition to operations in Iraq and Afghanistan, Bannister also deployed in support of Operation Uphold Democracy in Haiti, Operation Joint Guardian in the Balkans, and Operation Essential Harvest in Macedonia.

His awards and decorations include the Combat Infantry Badge, the Combat Action Badge, the Expert Infantryman Badge, the Master Parachutist Badge, the Ranger Tab and the Pathfinder Badge.