Four people have been arrested in connection with the shooting death of a security guard during an attempted robbery of an illegal casino in North Hollywood late last month, police said Wednesday.

The suspects were identified as Steven Hans Dunkel, 23, of Glendora, Matthew Scot Riley, 29, of Panorama City, Michael John Blankenship, 52, of Oxnard and Rudy Javier Madrid, 26, of North Hollywood.

Authorities believe they may be responsible for other armed robberies, “specifically to underground casinos,” the Los Angeles Police Department said in a news release.

The incident occurred around 3:40 a.m. May 31 at a nightclub along the 3300 block of Cahuenga Boulevard near Universal Studios.

Responding officers found the security guard suffering from multiple gunshot wounds, and he was pronounced dead at the scene, police said.

Officers also discovered an illegal gambling establishment inside the building.

A preliminary investigation indicated that two masked men entered the building from a back entrance while armed with rifles.

As the victims spotted the assailants, he removed a pistol from his waist, but one of the suspects grabbed a rifle and shot the victim multiple times, police said.

After searching the building, they fled the area without any money.

Around 30 people were inside the club at the time and were moved outside amid the investigation.

The suspects’ homes were searched and detectives believe the two rifles identified during the incident were recovered, as well as other evidence linking them to the crime.

It is unclear, however, what role each of the men played in the failed heist.

Anyone with additional information about the suspects is asked to call the LAPD’s Valley bureau homicide Detective Bucknell at 818-374-1928.