CHICAGO (CBS) – A Chicago firefighter was injured during a rescue of a resident from a blaze on the South Side on Saturday.

The firefighter was being treated at University of Chicago Medical Center and is in serious to critical condition, according to dispatch reports. A witness said he appeared to be overcome by smoke while entering the home.  Firefighters on the scene indicated he should be OK.

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An injured firefighter is treated at the scene. A witness said he appeared by be overcome by smoke. (CBS)

Three people, including a woman rescued from the second floor of the home, were sent to Jackson Park hospital. Their injuries were not believed to be serious.

The fire happened on the first floor of the home in the 8700 block of South Constance Avenue in the Calumet Heights neighborhood around 12:30 p.m.

Fire department officials say their colleague was injured trying to save an elderly woman trapped on the second floor.

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“During the rescue one fireman was injured and he had to be rescued out of the first floor,” said Deputy District Chief Jeffrey Mayer.

The cause of the fire, which was extinguished about an hour, is not known at this time.

Residents who escaped the blaze in their home. (CBS)

A next door neighbor, Wayne Looney-Gibson, came outside after seeing police and fire and said, “I saw them pulling my neighor out of the upstairs window.”

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His neighbors, who have lived in the house “all their life” were upset over the loss of their home. However, he old them, “Look forget the house, the most important this is everybody’s safe and a-okay.”