The situation began to unfold around 6 a.m. at a home on Clinton Place.
"A little after 6 a.m., Essex County Task Force was executing a narcotics warrant. Upon entering shots were fired. We have one person in custody. It's an ongoing scene still right now. A person is barricaded in," Newark Mayor Ras Baraka said. "I guess we have been here for a few hours and will wait it out until it prayerfully ends with the person turning himself in."
When the shots were fired, officers rushed people out of the home to safety and took up positions around the house.
"A lot of police, a lot of sirens, a lot of ambulances," said Charlie Jackson, an eyewitness. "It was just chaos."
It's not yet clear if someone inside the home or the police fired their weapons.
One person was later led away by police in handcuffs.
"I felt like I was in Iraq," said Michael Ellison, an eyewitness. "Helmets, trucks, all of this going on, it's crazy."
"Nobody hit, nobody hurt. By the grace of God, nobody injured. He's not injured. Neither are the police officers," Baraka said.
The mayor said police are in contact with the barricaded individual, and trying to talk him out of the home. They believe he is on the third floor and that he is alone.
"It is reckless, it's a dangerous situation. There are dangerous situations when executing search warrants, narcotics search warrants, particularly for people who don't want to go to jail," Baraka said. "We are just going to wait this gentlemen out and prayerfully it turns out that he turns himself in."
ALSO READ | Video shows massive blast as fireworks go off as they're being set up in Ocean City, Maryland
* More New Jersey news
* Send us a news tip
* Download the abc7NY app for breaking news alerts
* Follow us on YouTube