Gunshots were reported in a popular shopping mall in northern New Jersey and police were searching for the shooter Monday night.

Witnesses said multiple shots were fired in the Westfield Garden State Plaza Mall in Paramus shortly before closing time, CBS New York reported. However, police said they had found only one shell casing.

There were no immediate reports of injuries. The mall is located about 20 miles southwest of Manhattan.

As many as 200 law enforcement officers were on the scene. The mall was on lockdown and at least some people had been evacuated.

Witnesses told CBS New York that the gunman was armed with an assault rifle and walking around in full body armor and a helmet, but that could not be confirmed.

A woman who works at a store in the mall told CBS New York that she saw a man carrying a rifle.

"I saw him walk past our door, and he paused for a second and just looked inside the store, and he fired two more (shots)," she said. "He was all dressed in black from head to two with a helmet - I would say with a motorcycle helmet. I just froze. I didn't want to run, because he might maybe come after me. I just stood there."

A witness tweeted that the shooting occurred by Nordstrom department store on the second floor.

"As I was closing the store, I heard these loud fire-cracking noises. I never heard a gunshot before," an employee at the Michael Kors store who gave his name as Adam told WCBS 880 Radio. "I had a customer that shopped before, and she was running back into the store and saying, 'Someone has a gun.' So automatically, I ... started locking the gate and told the staff to go to the back with the customers even in the store."

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