UPDATED 11/05/13 1:47 a.m.
PARAMUS, N.J. (CBSNewYork) -- Police responded in force late Monday and early Tuesday, after a gunman fired several shots inside the Garden City Plaza Mall.
While there were no injuries reported, the gunman remained at large as of midnight Tuesday morning and was believed to have left the mall.
"At approximately 9:19 this evening, a single male entered the Garden State Plaza mall and fired several shots while the shopping mall was still open," Paramus police Chief Kenneth Ehrenberg said in a statement. "He was dressed in black wearing what is believed to be a motorcycle helmet. The weapon has not yet been recovered. No further shots were fired and there are no reported injuries."
At the scene, Paramus Mayor Rich LaBarbiera emphasized that everyone was safe.
"There has been no injuries, there has been no victims, and we are now searching the mall and sweeping it," LaBarbiera added at a news conference.
"We found one shell casing, which I believe was from a long-armed rifle," Paramus Office of Emergency Management deputy coordinator Jim Tedesco said on 1010 WINS.
Late Monday night and early Tuesday morning, agencies from all over New Jersey were going through the mall and sweeping the area. The mall was placed on lockdown, and crews were passing through in an attempt to evacuate the mall in a safe and orderly way.
Despite some people who reported more than one gunman, LaBarbiera said there was just one. He said the shooter was believed to have left the mall.
Authorities were also trying to make sure no one else was tied to the shooting.
As of 1:45 a.m., employees and shoppers continued to exit the mall. The staging area to pick them up had been set up at the Chili's parkikng lot adjacent to Route 17SB, WCBS 880's Jim Smith reported.
The mall will be closed throughout the day on Tuesday, WCBS 880 has learned.
The incident happened inside the mall beginning sometime before the mall in Paramus, N.J. closed for the night at 9:30 p.m.
Shots Fired At Garden State Plaza Mall In New Jersey
Upon being notified of the shooting, employees huddled in restrooms, in the backs of offices, and in stores. They were just coming out at 11 p.m., after SWAT teams and other police officers walked through area by area.
An estimated 200 police units were sent to the scene, and a mass-casualty unit was required.
Kimberly Recchia, who works at Bare Minerals, told WCBS 880 that she saw a man carrying a rifle and dressed in black a ski mask.
CBS 2's Dave Carlin reported witnesses the gunshots were fired on the second level, near Nordstrom, Talbots and J. Crew. As the gunshots were fired, mall security reportedly rushed through and told everyone inside, "Get out or you'll die."
Several sales associates said they looked the gunman in the eyes as he passed the J. Crew and Talbots stores.
"I saw him walk past our door, and he paused for a second and just looked inside the store, and he fired two more," one woman 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."
The man just walked past, and fired more shots afterward, the woman said.
"A man came down the aisle and he was firing gunshots with a rifle," she said. "First I heard it, then I saw him coming down the aisle, and then I saw people screaming, and then I just ran inside the back room."
"I was at the mall, and I saw a bunch of people running a bunch of people yelling, 'There's a shooting! There's a shooting!" said Joseph Elfar, a Rutgers student. "So me and my friend were at the Sprint store, and we start running out. We start running towards the exit, and a lot of people were running out the mall.
"As I was closing the store, I heard these loud fire-cracking noises. I never heard a gunshot before," Adam, an employee at the Michael Kors store, told WCBS 880. " ... 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."
Fernando Perez's daughter was at work inside the mall at the time of the shooting.
"Right now, she's telling me that she hears sound. She doesn't know what's going on. She hears movement in the vents. I keep telling her to turn the phone off and just wait for the police," Perez said.
Perez said her daughter said something about body armor, and reported that her manager saw it.
"I don't know what I'm feeling, because I don't think they'll let me in, and I'm just having to rely on fate; hope all goes well," he said.
Another employee described the gunman as a white male possibly in his late 20s, wearing a leather jacket, a motorcycle helmet with the visor up, motorcycle boots, and black jeans.
Another witness told CBS 2's Tracee Carrasco he saw people running from the scene.
"All I hear is, 'Gun, gun, gun! Run, Run, run!'" he said.
CBS News Senior Correspondent John Miller said police basically "don't really know what they have."
"They responded to an active shooter situation. They went into their active shooter protocols, which have been very well practiced by the Paramus P.D.; by the Bergen County sheriff's office; by the New Jersey State Police," Miller said. "In fact, they have used this very mall when it's been closed at night to do active shooter drills, practicing how they would respond to a situation like this."
But they did not find the kind of situation they expected, "which is numerous victims down or a gunman on the move," Miller said. "What they found is a gunman who was apparently gone – the search continues. No victims who were readily available, yet, numerous shell casings that indicate the shots that were fired all up and down the mall."
Based on information from authorities, it seemed that the gunman was taking shots "that seemed almost deliberately not aimed at people," Miller said.
Police were expected to look at many factors as they investigated, Miller said.
"A key factor is going to be three things here," Miller said. "One – to clear the scene. That's going to take all night. Two – to process that crime scene. What do those shell casings tell us? What evidence is there to gather? Did he tough something; is there a print? And three – to download and process all of the images from the dozens and dozens of digital security cameras he passed by to see? Is that visor up? We get a look at part of his face. Is that visor down? Is there something about his clothing that is distinctive, and as those cameras track him, do we see how he enters before the incident?"
The lockdown was expected to continue for several more hours as of early Tuesday morning.
Police asked that no members of the public come to the mall – including relatives or others seeking to pick up employees or shoppers onsite.
"Please allow the police to do their job," he said in the statement. "Arrangements will be made for persons to safely leave the scene."
Stay with CBSNewYork.com for more on this developing story.
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