A Southeast Michigan man has not been heard from in days, with the St. Clair County (Michigan) Sheriff's Office now asking the public to be on the lookout for him. 

Robert Leon Smith, 69, of Fort Gratiot, was last heard from Friday when he indicated to a family member that he was in trouble, the sheriff's office reported Tuesday. His phone has been turned off since then. 

Deputies used Flock license plate camera technology to locate his black 2012 Town and Country vehicle with Michigan plates traveling Monday on I-96 near Davison; but the whereabouts of Smith are still unknown. 

Smith is diabetic and does not have his insulin with him, the report said. 

St. Clair County deputies ask that anyone who has seen Smith recently or knows his location contact Central Dispatch at 810-985-8115.