WINDSOR LOCKS, Conn. (AP) — A World War II-era bomber plane crashed in a fireball as it tried to land Wednesday at New England’s second-busiest airport, and a fire-and-rescue operation was underway, officials said.

A spokesman for Gov. Ned Lamont confirmed the crash of the B-17 plane at Bradley International Airport north of Hartford, Connecticut.

A fire with black smoke rose from near the airport as emergency crews responded. The airport said in a message on Twitter that it has closed.

It wasn’t clear how many people were on board or where the plane was going, Lamont spokesman Max Reiss said. The New England Air Museum is near the airport.

The Federal Aviation Administration said on Twitter that the B-17 had been trying to land. It was civilian-registered and not flown by the military, the FAA said.

Airport officials said the plane was associated with the Collings Foundation, an educational group that brought its “Wings of Freedom” vintage aircraft display to Bradley International Airport this week.

A representative of the group could not immediately confirm any information about the crash but said it would issue a statement.

Antonio Arreguin said he had parked at a construction site near the airport for breakfast when he heard an explosion. He said he did not see the plane but could feel the heat from the fire, which was about 250 yards away.

“In front of me, I see this big ball of orange fire, and I knew something happened,” he said. “The ball of fire was very big.”

A smaller explosion followed about a minute after the first blast, he said. He saw emergency crews scrambling within seconds.