AURORA, Ill. (CBS)– An 85-year-old man was found dead in a fire in a senior living facility in Aurora just after midnight Monday.

Aurora firefighters were called at 12:03 a.m. to an automatic fire alarm at the seven-story Constitution House senior living facility at 401 N. Constitution Dr.

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Firefighters checked the alarm panel and found a fourth-floor smoke detector activated. Upon reaching the fourth floor, firefighters found light smoke throughout and called a second alarm – bringing a total of 40 firefighters top the scene.

Residents were advised to stay in their apartments as fire crews searched for the site of the fire. They found smoke coming from one apartment and entered, quickly extinguishing the blaze.

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But at the scene, they found an 85-year-old man dead, the fire department said.

“It’s very scary, you know, and I thought the alarms would never go off – it lasted so long, you know,” said building resident Ann Bolden. “I immediately got dressed. I went and looked out in the hall, so far there was nobody.”

The fire was contained to the man’s apartment, though some units sustained water damage. But nobody was displaced, the fire department said.

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The cause of the fire was under investigation Monday afternoon. The estimated total dollar loss was $35,000.