The man arrested for allegedly robbing a bank in Douglas on Monday was caught, in part, because he borrowed his girlfriend's car with a GPS tracking system, according to the criminal complaint filed by the FBI on Wednesday.

Law enforcement agencies responded to a 2:30 p.m. call about a robbery of the Points West Community Bank on East Richards Street in Douglas.

A man wearing a black-hooded zip-up jacket and black hat entered the bank and gave a note to a teller: "'I have a Gun. Put the money the Bag now. Don't try anything.'"

The teller put $4,300 in cash in a Crown Royal liquor bag, and the man left the bank.

Witnesses did not see a gun.

Meanwhile, a Cheyenne woman called Douglas police to tell them her boyfriend had borrowed her car and was to have returned it to her by Sunday. Because he had not returned it, she thought he may have stolen it.

Her car, however, had a Global Positioning System device that indicated it was in Douglas near a building with school buses nearby, according to the criminal complaint. "Points West is located immediately west of a school bus storage area and in close proximity to a public school."

Later Monday, a Converse County Sheriff's deputy stopped a car matching the girlfriend's description on Interstate 25 near Douglas, and Mathis was identified as the driver.

After obtaining a warrant, law enforcement officers searched the car and found a Crown Royal bag, $4,300 in cash with wraps from Points West Community Bank, and a notebook with paper matching the paper used in the robbery. On one page, officers saw indentations from writing on the previous page that matched the words on the note handed to the teller.

Douglas Police arrested Mathis.

The case has been turned over to the federal government for prosecution. If convicted, Mathis faces up to 20 years imprisonment.

A clerk at the U.S. District Court in Casper said a date for Mathis' initial appearance has not been set.

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