( CNN ) -- A shooter opened fire at a New Jersey mall late Monday , sending panic through the shopping center and igniting a massive police response . The gunman inside Westfield Garden State Plaza Mall in Paramus , New Jersey , had not yet been found during a sweep of the shopping center by Bergen County SWAT , said county Chief of Staff Jeanne Baratta . But authorities have identified a possible suspect , New Jersey State Police Sgt . Joe Lettieri said . Authorities swept through the mall store-by-store late into the night . Mayor Rich LaBarbiera said there have been no injuries , and authorities believe the gunman is no longer in the mall . At least one gunman is said to have fired shots at security cameras , the state police said . A single shell casing has been found , a Bergen County emergency management official said . Eddie Kahmann , who works inside the mall , told CNN he heard 6 or 7 gunshots around 9:20 p.m . ET . `` There was just people running like crazy , so I quickly just closed my doors , ran to the back , turned off all the lights , music and everything , just to stay hidden , '' he said . Kahmann spoke from inside the mall , one of the largest shopping centers in the New York City area . Allie Cozic , another mall employee , said she saw `` someone dressed in all black , carrying a large gun , walk past our store . '' She said she heard loud bangs about 10 minutes before her store was set to close for the night . `` It was just chaos . Everyone was just kind of running to wherever they could , '' Cozic said . `` It was almost like when you 're watching a horror movie and the killer is walking slowly -- that 's what it seemed like . He was wearing all black , it almost looked like body armor of some kind . As soon as I saw the gun , I just turned and ran , '' she said . There is a large police presence at the mall , which was set to close at 9:30 p.m . ET . There are about 20 vehicles both marked and unmarked . The FBI , including an FBI SWAT team , was also on the scene . `` There is a massive response from several agencies , '' according to a law enforcement source with knowledge of the investigation . Police were putting on flak jackets and bringing out assault weapons . People were pushed away from the mall and were telling CNN that they 've been told the shopping center was on lockdown . Westfield Garden State Plaza is located some 12 miles from Manhattan . It boasts of being home to nearly 300 specialty shops and boutiques . CNN 's Sarah Aarthun , Scott Garber and Laura Dolan contributed to this report .
NEW : The police say a possible suspect has been identified . Northeast : Police say the gunman has left the building . A store - by - store sweep of the Garden State Plaza is ongoing . There are no immediate reports of injuries .