Updated 8/4/12 at 2:42 p.m.

CHICAGO (STMW) - A man who had recently moved to Chicago from Puerto Rico was stabbed to death in a fight with a group of people in the River North area early Saturday.

About 3:45 a.m., the victim, who police say was 20 years old, was with some other people in a van at the BP gas station at LaSalle and Ontario. A “party bus” pulled into the gas station, gang signs were flashed, and a physical altercation ensued, a law enforcement source said.

The van drove off and the man fled on foot with people from the party bus following him on foot. When the others in the van noticed that he was not in the van with them, they turned back and found the man in the 600 block of North LaSalle Street, suffering from multiple stab wounds, the source said.

A relative of his was also stabbed at that location, according to police. That person was treated at a hospital and released.

The victim, whose identity was not available as of later Saturday morning, was taken to Northwestern Memorial Hospital, where he was pronounced dead at 4:18 a.m., according to the Cook County Medical Examiner’s office.

The source said the victim, who had recently moved to Chicago from Puerto Rico, has no record of a criminal history. Detectives could not immediately confirm a report of gang signs being flashed in the encounter in the gas station.

The gas station where the fight occurred is in a busy area of the River North neighborhood, across from the “Rock n’ Roll” McDonald’s restaurant and a few blocks from the Ontario Street expressway feeder ramp.

No one is in custody and Area Central detectives are investigating.

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