Washington, Dec 27 (IANS): Three people were killed after a person opened fire at a bowling alley in the US state of Illinois, police said, adding a suspect was currently in custody.

The incident, which also left three other people injured, took place on Saturday evening at the bowling alley located in Rockford, about 140 km away from Chicago, Xinhua news agency.

At least two teenagers were among those shot, Rockford Police Chief Dan O'Shea said at a news briefing.

The ages and conditions of the surviving victims were not immediately known, nor were the ages of the victims who were killed, local media reported.

The Rockford Police Department urged people to stay away from the area near the bowling alley.

The police believe the shooting was a random attack, O'Shea said at the briefing.

Some people were shot outside the building and some inside, he added.

The suspect was still in the building when the police came.

"No officers fired their weapons we know of at this point," O'Shea said.

An investigation is underway.