MARTINSVILLE, Va. – Steve Lawson, a popular NASCAR official, was found dead in his hotel room Sunday morning, NASCAR officials said. He was 51.

The cause of death was not announced. Lawson, of Rockford, Ill., worked as an official for stock car racing’s governing body for more than a decade, most recently as a safety inspector in the Sprint Cup Series.

He was scheduled to work at Sunday’s TUMS Quikpak 500 at Martinsville Speedway. A moment of silence was held before the race.

He is the third NASCAR official to die this year. Brienne Davis, a 28-year-old and one of NASCAR’s few full-time female inspectors, was killed in a car accident in April, and Steve Peterson, a longtime technical director, died in his home in July at age 58.