John Riley and Greg Toppo

USA TODAY

An 18-year-old Virginia man was seriously injured in a blast in New York's Central Park Sunday that police say could have been caused by homemade fireworks.

Police identified the injured man as Connor Golden of Fairfax, Va.

WABC-TV reported that he was critically injured by the explosion, which it said occurred at about 11 a.m. ET as he climbed off a rock near Fifth Avenue and East 62nd Street.

An unnamed eyewitness said Golden was climbing on a rock structure when he stepped on something that exploded, WCBS Newsradio 880 reported. He was undergoing surgery on his left foot at Bellevue Hospital, where he was reported in stable condition.

At a briefing Sunday afternoon, NYPD Deputy Chief John O'Connell said the blast "could have been an experiment with fireworks or homemade explosives." A few hours later, police spokesman J. Peter Donald tweeted, "what caused the explosion was likely homemade fireworks or something similar."

Lt. Mark Torre, head of the city's bomb squad, told the New York Post, “This is a time of a year where typically we will see a lot of experimentation — explosive experimenters, if you will. Their goal is to make a loud noise, maybe make a flash. They like to make noise and sort of play with fireworks, and it’s even better if they can make their own.”

Police dogs were canvassing the park for more possible explosives, the AP reported, and police were also examining a car parked at Newark Airport that the victim used to drive to New York, sources told the New York Daily News.

The explosive appeared to have been in the area for more than a day, Torre told the Daily News. Two of Golden's friends told police they had no fireworks or other explosives.

One witness said the blast sounded “like a cannon.”

One of Golden's friends, Thomas Hinds, 20, told the Daily News that he had just stepped off a large rock when the blast went off behind him.

“I got down the hill and boom, my ears were ringing. I felt a wave, a gust hit me in the back,” Hinds said. “I turned around and saw him on the ground with his foot bleeding."

Hinds added, "It just demolished his foot."

An unnamed official told the New York Post that the explosive was in a brown bag and didn't appear to be designed to be pressure-sensitive.

Torre told the Post that forensic evidence suggested it was "not meant go off by someone stepping on it."

The explosion was heard by attendees of Elie Wiesel’s funeral on E. 61st St., the Daily News reported, though there was no sign the blast was related to the memorial for the Pulitzer Prize-winning Holocaust survivor.

New York City Mayor Bill de Blasio on Sunday tweeted, "Dangerous incident in Central Park today. Fireworks are fun — but let's leave them to the professionals. Stay safe."