New York City: A young man who opened fire at a New Jersey mall has been found dead, an official said early Tuesday.

No one was hurt in the incident in Paramus, about 30 kilometres, from New York City.

The gunman was found in an under-construction area of Garden State Plaza mall, Bergen County prosecutor John Molinelli said, according to local TV affiliate CBS New York.

He said the suspect, identified as 20-year-old Richard Shoop, had killed himself with the same weapon he used in the mall and that a note had been found.

“There was no one that was injured in this incident, there was no individual that was struck by anything other than Mr Shoop taking his own life,” Molinelli said. “I do not believe that Mr Shoop intended to come out of here alive.”

Authorities had put the shopping mall on lockdown late Monday after the gunman opened fire, sending shoppers and employees scurrying for cover.

“He came to the mall, fired what is at least six rounds at random, striking several different locations in the mall,” Molinelli said.

“The bullets were fired into an escalator, into an elevator area. There was some property of retailers that was struck — a facade area — and there were a couple of shots that were shot straight up,” he added.

Many stores scrambled to close their gates at the popular mall in a suburban area.

Molinelli said the weapon Shoop used was modified to look like an AK-47 assault rifle but said “it was a lawful weapon owned by his brother,” adding investigators believe Shoop stole the gun from his brother earlier in the day.

The incident initially recalled September’s tragedy at a shopping mall in Nairobi, Kenya, where an attack claimed by Somalia’s Al Qaida-linked Shebab killed at least 67 people.

It was the latest in the epidemic of gun violence plaguing the United States.

On Friday a gunman opened fire at Los Angeles airport and killed a Transportation Security Administration agent.

The FBI said he was carrying a note saying he planned to kill multiple officers. The 23-year-old suspect faces a possible death penalty on charges of murdering a federal officer.

On October 24, a US soldier who opened fire at a Tennessee recruiting centre after being reprimanded for misconduct was indicted on attempted murder charges.

Three members of the Tennessee National Guard were struck in the crossfire but none suffered serious injuries.

The October 24 shooting came a month after a massacre left 13 people dead, including the gunman, at a major Navy facility in Washington, D.C. The gunman was shot dead.

A shooting spree at four homes and a gas station in Texas left five people dead and a suspect in custody on October 29.

And in a particularly alarming case, an 11-year-old US student appeared in court on October 24 on suspicion of attempted murder after bringing a handgun and 400 rounds of ammunition into school.

In the latest in a spate of incidents in US schools, the boy also allegedly brought “multiple” knives to the Frontier Middle School in Vancouver, in Washington state.

That same week police in California shot and killed a 13-year-old boy who was carrying a pellet gun that officers said looked like an assault rifle.

The child was walking down a street in the northern town of Santa Rosa when sheriff’s deputies saw him carrying what appeared to be a rifle.

They ordered him to drop it “and at some point immediately thereafter, the deputies fired several rounds from their handguns at the subject striking him several times,” according to a statement from the Sonoma county sheriff’s office.