PAULSBORO, N.J. (WPVI) – Authorities in Gloucester County say more than one gunman opened fire into a crowd of people after a gathering, leaving five people injured.

It happened after 1 a.m. Saturday at the Paulsboro Elks Club at West Buck and Pennline streets in Paulsboro. The gunfire erupted after an event initially described as a rap concert and later said to be a birthday party.

Investigators say a male was punched and knocked to the ground outside the club, and then shots were fired.

Three males and a female were hit by bullets. A fifth person, a male, tripped while running from the gunfire and suffered a head injury.

Some of the injured were taken to Inspira Medical Center in Woodbury, N.J. Others were taken to Cooper University Hospital in Camden N.J. for treatment.

Initial reports indicated three of the victims were critically injured. The Gloucester County Prosecutor’s Office later said none of the injuries are considered life-threatening.

Detectives are reviewing surveillance video in an effort to determine who fired the shots, and why. Paulsboro Police Chief Vernon Marinol said the shootings are believed to be an isolated incident between individuals who knew each other, and that there is no threat to the wider community.

Investigators said that based on ballistic evidence at the scene, it appears more than one shooter opened fire.