FAIRFIELD — Police are seeking the public’s help in identifying a man who robbed a Fairfield Dunkin’ Donuts early Tuesday morning.

The robbery happened around 2 a.m. Tuesday when a black man, who police described as having a “thin build, in his 40s, wearing a red jacket and hat,” walked in to the Dunkin’ Donuts at 593 Post Road and demanded the money out of the cash register.

The man implied he had a gun, though no weapon was displayed, and he threatened to shoot the cashier, police said.

An undetermined amount of cash was taken from the register, police said.

By the time police arrived, the man had fled the scene. A K9 track of the suspect was unsuccessful.

No one was injured in the incident.

Detectives are still investigating the robbery. They ask anyone with information to contact the Detective Bureau at 203-254-4840.