Chaos reigned in downtown Orlando when a 17-year-old gunman allegedly opened fire during a Halloween celebration early Friday – and many partygoers feared they would be killed in the attack.

“It was the most scared I’ve ever been,” Joey Herrera, 22, who attended the celebration with his girlfriend and several other friends, told The Post.

“I was afraid of being killed and I didn’t want to die that way.”

As the sound of gunfire echoed through the streets, people fled for safety, hiding in nearby stores or running down side streets.

At the Mondrian Apartments, an upscale high-rise just a block from the party, frightened partygoers crowded the lobby as police cars whizzed by. The complex, normally closed to non-residents, opened its doors to those seeking safety.

“There was chaos, panic and terror,” said a receptionist. “The scariest thing I can remember.”

Suspected teenage gunman Jaylen Dwayne Edgar walks through crowded streets in a yellow shirt and backpack before he starts shooting, sending costumed revelers fleeing for their lives, a harrowing video released Friday by Orlando police shows was published.

At least two people were killed and six others were injured in the mass shooting, police said.

Edgar allegedly tried to flee the scene, but a police officer who saw him pull the trigger immediately tackled him to the ground alone before three other officers pounced on him.

During an early morning news conference, Orlando Police Chief Eric Smith said Florida’s new constitutional carry law has changed the way officers keep the area safe.

“We used to do closures and we had the dogs and all that,” Smith said. “That all went away when the law changed and basically you can carry a gun on a public street as long as you meet certain criteria. When that changed, we can’t do that anymore.”

“We couldn’t do the dogs we had downtown anymore,” Smith continued.

“We’re working with the city and the downtown clubs to see if there’s anything else we can do to keep things safe down there. With so many people down there, we have no idea what it is about them.”

A motive has not yet been announced and the names of the victims have not been released. It is unclear whether Edgar has retained an attorney to speak on his behalf.