PORTSMOUTH, N.H. (AP/WHDH) — Firefighters say three buildings collapsed following a large fire Monday morning in downtown Portsmouth, New Hampshire.

The fire spread from a three-story building that houses a restaurant to neighboring buildings that house several apartments.

RELATED: Portsmouth residents react after massive blaze reduces buildings to rubble

More than 100 firefighters from three different states responded to the scene. The buildings were reduced to a pile of rubble.

Some residents had to be rescued due to fierce flames and heavy smoke.

“The victims were trapped and they could not come down the main stairwell,” Portsmouth Fire Chief Steven Achilles said.

The blaze broke out at about 12:30 a.m. in a building that houses the 34-year-old State Street Saloon near the city’s Market Square, the heart of its downtown area with shops, restaurants and many historic buildings.

“This goes above and beyond what we’ve had in recent years,” Achilles said of the fire.

Investigators believe the fire started in the kitchen. No injuries were reported.

The Red Cross is assisting those displaced by the fire.

The cause of the fire is under investigation.

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