Army Spc. Jeffrey A. Williams, 20, a 2003 graduate of Wheaton Warrenville South High School, died Monday in Tal Afar when an explosive device detonated near his combat patrol, the Defense Department said.

Williams, who his mother said was a combat medic, was assigned to the Support Squadron, 3rd Armored Cavalry Regiment, based at Fort Carson.

Williams, the oldest of four boys, enlisted in the Army just days after he graduated from high school, said his mother, Sandra Smith of Mansfield, Texas.

"He was a leader, he wasn't a follower," said Smith, whose family moved to Texas after her son joined the Army. "The boys are really having a hard time. Every last one of the kids is having a hard time because they really looked up to Jeffrey."