DARIEN — For the second time in the span of a month, a bank in Darien was robbed Tuesday by a man who passed tellers a note demanding money.

Police responded to the Chase Bank at 165 Noroton Ave. around 1 p.m. July 11. Witnesses told officers a tall, black man had entered the bank and handed an employee a note.

“The note implied that that the male had a firearm, but no weapon was ever displayed,” according to a police report. An undisclosed amount of money was handed over and the man exited the bank without incident. He was last seen in an adjacent parking lot on Heights Road, getting into a white sedan, possibly with New Jersey license plates.

Darien Police are working with the Federal Bureau of Investigation to identify the suspect, pictures of whom were captured by the bank’s security cameras.

On June 12, the Chase Bank on Post Road in Darien was robbed under similar circumstances. According to police, a black man in his 20s or 30s — described as between 5 feet 9 inches and 6 feet tall, heavyset, and bearded — walked into the bank, passed the teller a note demanding money, and left without incident.

On July 2, a TD Bank branch on the Post Road in Westport was robbed using the same technique. A man handed over a note demanding money, that implied he may have a weapon. Money was exchanged, and the man left. He was described as a black male, approximately 6 feet 1 inches tall with a heavy build, scruffy beard and wearing a Chicago Bulls baseball cap.

Darien Detective James Palmieri said he couldn’t confirm whether the three robberies were related.

“We’re obviously considering the similarities,” said Palmieri.

The Darien Police are asking anyone who has any information or recognizes the pictured suspect to call the Darien Police Detective Bureau at 203-662-5330. Westport police are also actively investigating and urged anyone with information to call the Westport Detective Bureau at 203-341-6080.