Federal authorities are asking the public for help in the search for a man who robbed a Chase bank earlier this year in the Loop.

The man entered the bank about 5 p.m. May 22 at 35 W. Wacker Drive and gave the teller a note that said he had a bomb in a suitcase, according to Chicago police and the FBI. The teller gave him an unknown amount of money before he fled on foot.

Surveillance video released Friday by the FBI shows the suspect has a “distinctive gait.”

He is described as a man in his 40s or 50s with a heavy build, the FBI said. He wore a white shirt, a brown hat and dark shorts.

Anyone with information about the robbery is asked to contact the FBI’s Chicago Field Office at (312) 421-6700.

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