McLean baseball Coach John Thomas resigned last week after being charged with marijuana possession during a routine traffic stop, school and police officials said Tuesday afternoon.

Thomas, 35, was stopped for displaying an improper vehicle registration at about 2:45 p.m. on Feb. 5 on the exit onto I-66 from eastbound Route 7, Fairfax County police spokesperson Lucy Caldwell said.

During that stop police discovered marijuana. Thomas has been charged with possession of the drug, a misdemeanor that can carry a year-long prison sentence and/or a $2,500 fine. He also was charged with driving without a license.

McLean Athletic Director Jim Patrick said that Thomas resigned Friday as coach but continues to teach special education at the school. Patrick said that assistant coach Ray Zdancewicz would take over as interim head coach, with returning assistant Jason McMahon also on the staff. Practice begins Feb. 18.

Thomas was McLean’s head coach for seven seasons. His teams went 108-53 and won the Virginia AAA Liberty District title in 2009.

John Thomas resigned as McLean’s baseball coach but will remain at the school where he teaches special education. (John McDonnell/THE WASHINGTON POST)

Thomas, a McLean graduate who played at the University of Virginia, had been serving as president of the Northern Region Baseball Coaches Association. He could not be reached for comment.