Two Maryland men chose the wrong bar to try and rob when they unexpectedly discovered it was full of police officers.

Police in Woodlawn, Maryland, arrested Joseph McInnis III, 21, and Tyree McCoy, 22, after the pair walked into Monaghan’s Pub waving guns and demanding money from the cash register. The suspects grabbed the cash and ran out of the bar, WBAL TV 11 reported.

Unfortunately for the would-be crooks, the bar was filled with police officers attending a retirement party for Sergeant David Neral, a nearly 30-year veteran Woodlawn police officer. After being robbed at gunpoint, the employees quickly told the officers what had happened.

Several officers then followed the thieves and detained the pair a few blocks away.

“I’m sure that they weren’t planning on there being a large room filled with police officers,” said Baltimore County police Officer Jennifer Peach told WBAL.

Bar owner Jack Milani said he was surprised anyone would be foolish enough to try and rob Monaghan’s Pub because it is a well-known hangout for local police officers.

“It’s kind of odd you would even attempt it,” Milani told the Baltimore Sun. “[Officers] are always in here. There was a decent amount of them.”

The suspects were charged with armed robbery, theft, and possession of a handgun among other charges. They are currently being held without bond at the Baltimore County Detention Center.

Follow Warner Todd Huston on Twitter @warnerthuston