A Fort Bragg soldier died Tuesday after he collapsed during physical training.

Sergeant Robert “Robbie” Thornton Jr., 29, of Cairo, Georgia, was assigned to the 528th Sustainment Brigade as a power-generation equipment repairer. He was reportedly running on Ardennes Drive, which was closed to traffic, for physical training when he suddenly collapsed.

A spokesman for the unit said that several soldiers attempted to help the man, who was rushed to Womack Army Medical Center.

The cause of death is unknown, officials said. His death is under investigation.

The 528th Sustainment Brigade is part of the 1st Special Forces Command at Fort Bragg, according to Fay Observer. Its soldiers support Special Forces, civil affairs and psychological operations soldiers around the world.

Thornton had been part of the brigade’s 112th Signal Battalion since January.

“We mourn the loss of this dedicated soldier and our thoughts and prayers are with his family,” said Lt. Col. Shaw Pick, the soldier’s battalion commander. “He was a member of our team, and his life was spent in service to his family, his friends and his country.”

Thornton is survived by his wife, Danielle, and two children, Jaylen and Kinsley.

He enlisted in the Army in 2012 and trained at Fort Benning, Georgia, and Fort Lee, Virginia. He previously served with units at Benning and Yongsan Garrison, South Korea.

Thornton’s awards and decorations include the Army Commendation Medal with two Oak Leaf Clusters, Army Achievement Medal with one Oak Leaf Cluster, Army Good Conduct Medal, National Defense Medal, Global War on Terrorism Service Medal, Korean Defense Service Medal, Noncommissioned Officer Professional Development Ribbon, Army Service Ribbon, Overseas Service Ribbon, Parachutist Badge and the Air Assault Badge.