BOSTON (CBS) – Firefighters rescued a father and son from a burning home in Boston Monday afternoon. The younger man is in serious condition.

The fire at the well-known dental office on Babson Street in Mattapan quickly went to four alarms.

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When fire crews first arrived, it was a race against time to get everyone out.

“The father met the engine companies out front,” Boston Fire Commissioner Joseph Finn said. “He appeared to be dazed and confused. He’d taken some smoke.”

Surveillance video shows Walter Holman, an elderly dentist, run out of his home and practice and around the corner to try and save his son who was trapped on the first floor.

Firefighters battle blaze in Mattapan (WBZ-TV)

Firefighters battle blaze in Mattapan (WBZ-TV)

Finn said firefighters had a hard time getting into the building. “It seems like the elderly gentleman kind of hoarded everything so it’s difficult trying to get around,” Finn said.

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Officials say the son was in cardiac arrest when they found him. He and his father were rushed to area hospitals and a firefighter also suffered a minor injury when he fell in a hole in the floor.

Boston firefighters battle 4-alarm in Mattapan (WBZ-TV)

Boston firefighters battle 4-alarm in Mattapan (WBZ-TV)

Firefighters believe a piece of dental equipment caused the fire.

“I was just a little worried because he had been in there for a little while before they found him,” said Stacey Thomas who owns a nearby gas station and has known the family for years.

“So to have him be in here this morning and be talking to him and then this afternoon for this to happen, it’s not a good feeling,” Thomas said. “I just hope that the son’s going to be OK.”

The son was taken to the hospital in serious condition.

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Finn said firefighters were extra cautious in the building because they were unsure if there was gas or any other hazardous materials in the dentist office.