Chatham-Kent police are asking for the public's help.
Police say officers were called to the Royal Bank on King Street West in Chatham on Thursday around 3pm for a report of a robbery.
According to police, a man entered the bank and demanded cash from a teller.
Police say the man received an undisclosed amount of money and fled the scene on a white mountain bike.
No one inside of the bank was physically hurt.
Anyone with information is asked to call Chatham-Kent police or Crime Stoppers.