A massive RV explosion in Massachusetts seriously injured three men, setting at least one victim on fire, and sending them to hospitals Tuesday afternoon, local authorities and witnesses confirmed.

Firefighters responded to a home on Walker Road in the city of Peabody in Essex County after multiple 911 calls reporting the blast, a Peabody Fire Department emergency dispatcher told USA TODAY Wednesday.

The city is about two miles northwest of Salem.

The dispatcher confirmed three victims who suffered burns in the blaze were taken to hospitals.

Peabody Fire Chief Jay Dowling told WBTS-TV, crews arrived to find the RV fully involved, found three male victims conscious and alert and extinguished the blaze.

Dowling said two victims, men in their 40s and 70s, were flown to Massachusetts General Hospital in Boston to be treated for burns and a man in his 20s was taken by ambulance to a hospital in Burlington, a city about 17 miles west.

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Cause of Peabody RV explosion under investigation

The cause and origin of the fire were not immediately known.

Authorities confirmed fire officials are investigating reports the men were working on the vehicle at the time.

USA TODAY has reached out to the Peabody fire chief.

Fire in Peabody 'rocked the entire neighborhood'

Neighbors reported a grandfather, son and grandson were preparing an RV for a trip to the Grand Canyon when the vehicle exploded and "rocked the entire neighborhood, "WBZ-TV reported.

Ring doorbell footage captured the explosion, the outlet reported, as well as a man "running out of the RV on fire before rolling on the ground."

“We heard a big explosion," neighbor John O’Donnell recalled to the outlet. "I looked out the window and saw tons of smoke going up into the sky. You could see the flames over the house across the street from me, and I ran out and down the street and saw the RV on fire."

Natalie Neysa Alund is a senior reporter for USA TODAY. Reach her at [email protected] and follow her on X @nataliealund.