BALTIMORE (WJZ) — Three people were killed in a fire Saturday night at an Anne Arundel County building that was being used as a group home.

Fire crews were called out just after 10:45 p.m., after authorities got several 911 calls about a fire in the 7900 block of Stone Hearth Rd., in Severn.

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“We knew the fire was intense before we got here because we started receiving multiple calls from the homes in the area reporting the fire,” said Captain Russ Davies of the Anne Arundel County Fire Department. “When our first units got here, they did have heavy fire coming from the back of the home.”

Responding firefighters saw heavy flames coming from the back of the house. Several people were able to get out safely, but firefighters were told that there were still people inside.

“It was like a big boom. And it shook the house, so we ran out, I thought somebody ran into a house or something, then that’s when we saw the flames,” neighbor Matthew Cohen said. “These neighbors are really good. They all chipped in, and really selflessly tried to run in that house. A lot of people tried to run in that house to get them people out.”

Fire crews went inside to search for people, and found a man, who was declared dead at the scene.

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During further searches of the home, two more people were found dead inside.

The names of the victims have not been identified at this time, but fire officials say two were residents of the group home operated by the Arundel Lodge, and one was a worker.

It took about an hour for firefighters to put the flames out.

The ATF is on scene to assist with the investigation.

The cause of the fire remains undetermined, investigators are continuing their investigation. Investigators are asking anyone with video or pictures from the fire to contact them at (410) 222-TIPS.

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