Emma Robertson, whose 38-year-old son Christopher disappeared without a trace more than three weeks ago, is asking anyone who may have seen him to contact law enforcement agencies.
She said Christopher may have asked someone for a ride because he was not driving his own car. Ms. Robertson described her son as stocky, 5 feet 11 inches tall, with dark curly hair and brown eyes.
When last seen, he was wearing a black sweatsuit. He has a tattoo of a keyhole on his right arm.
Ms. Robertson said Christopher had been profoundly depressed since being diagnosed with bone marrow cancer.
Since his disappearance he has made no contact with friends or family members.