The 20-year-old suspected in a New Jersey mall shooting was found dead early Tuesday of a self-inflicted gunshot wound, authorities said in a news conference.

The body of Richard Shoop, 20, of Teaneck, was found in a storage area inside the Garden State Plaza Mall in Paramus.

Officials don’t believe Shoop intended to hurt anyone, only himself.

Authorities say Shoop left a note at his home – and that the gun he fired was stolen, legally registered to his brother.

The gunman has a history of drug abuse, Bergen County Prosecutor John Molinelli said.

“Hard drugs … everything,” Molinelli said. “MDMA (Molly) I think was his drug of choice.”

The developments bring finality to a frantic night that left shoppers panicked and scrambling – with the gunman terrorizing the huge mall by casually firing shots in the air.

The situation unfolded at about 9:20 p.m., when the gunman, clad in black body armor and a biker helmet, taunted workers and shoppers as he squeezed the trigger.

“He was waving at people, doing wise ass things,” said a worker at a mall kiosk who gave his name as Michael.

“People were running and screaming. I just ran. It happened so fast.”

The crazed gunman did not appear to target specific individuals, instead firing into the air and at security cameras.

“He didn’t take shots at anybody, he was just shooting in the air,” the worker said.

Another witness said the shooter was gently telling people that he wasn’t going to hurt anyone as he fired shots around them.

“He was just walking around the mall telling everybody that he was not going to hurt anybody,” said Samantha Davis, 20.

“He seemed very calm — like the f–king Halloween guy Michael Myers.”

Police worked to clear the two million square feet of mall, located about 15 miles northwest of Manhattan.

A massive manhunt followed the shooting. Cops in body armor swarmed the home in Teaneck, New Jersey, where they were greeted by a pit bull dog.

Officials said there was only one confirmed shell casing recovered, but witnesses reported hearing multiple shots.

“I could hear the shots, they sounded like firecrackers going off one after the other,” said Mercedez Heggs, of Clifton, New Jersey.

“He was wearing a leather jacket and a black biker helmet. I saw his big shot gun.”

Heggs, who works at the Uniqlo clothing store, said that security acted quickly to address the situation.

“I made sure to get all my people out off the store then we started running out of the mall with our hands up along with everyone else,” she said.

“Hordes of people in the mall were screaming and running. I didn’t see any blood or injuries thank God.”

Another worker at Uniqlo said they used the bank across the way to hide from the shots.

“We just dropped our things and got going,” said Andrew Flores, 24. “We ran towards Bank of America across the street and used it as a base.

A massive police presence swarmed the mall, as they tried to apprehend the shooter.

“I’ve never seen this many cops before,” Flores said. “There are hundreds of them here. The guy was wearing body armor. It’s insane. This is such a scary situation.”

Inside the Nordstrom close to where the shooting occurred, shoppers and employees huddled inside a stock room for safety.

A Nordstrom employee, however, told The Post that no one in the store was injured.

“Everyone is good,” the employee said. “We’re just waiting for the police to clear us so we could go home.”

Additional reporting by Dana Sauchelli, Larry Celona, Bruce Golding, Chris Perez, Jamie Schram and Dan Good