Police are asking for the public’s help to find a Herndon, Virginia, man who has been missing since Monday night.

Virginia State Police issued a regionwide critical missing persons bulletin on behalf of the Herndon Police Department for the public to be on the lookout for 79-year-old Leonard Thompson.

Thompson was last seen on surveillance video pumping gas at an Exxon on Pacific Boulevard in Sterling around 8:30 p.m. Monday.

His car was discovered around 3:30 a.m. Tuesday morning in a southbound travel lane on Interstate 81 north of Roanoke, near the town of Troutville. The car had a flat tire, and the keys were missing.

Thompson was nowhere to be found, officials said.

Family members told D.C. News Now that Thompson had attended a funeral Monday evening and then had dinner with some friends. They also said he was acting normally.

Thompson is diabetic and without his medication, according to D.C. News Now.

He is described as a white man who is 5 feet, 10 inches tall and about 160 pounds. He has white hair and wears glasses.

Police ask that anyone with information immediately call the Herndon Police Department at (703) 435-6846 or contact the Virginia State Police.