By Mugo Odigwe

CHICAGO (CBS)– Three kids, left home alone, were rescued from an apartment fire in Washington Park.

One of the children threw *this mattress out of the window… And jumped.

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A fire broke out in the apartment, located near 61st Street and Wabash Avenue around 11:30 p.m. Wednesday.

The Chicago Fire Department said a neighbor quickly threw a mattress out the window and a 10-year-old girl jumped to the ground. Earlier information had indicated it was the girl who threw the mattress, but the Office of Fire Investigations concluded otherwise.

A 4-year-old boy was about to jump, but firefighters arrived in time to get him out with a ladder.

Firefighters also rescued a 2-year-old boy.

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The children are being treated at the University of Chicago’s Comer Children’s Hospital. CFD said they are in serious condition.

Neighbors said there was a lot of smoke in the building.

“It started smoking,” Neighbor Dale Kendrick said. “We heard the alarm go off and my mama just told us, ‘everybody get out get out, it’s a fire.’ She called 9-1-1 and as we were running downstairs we saw smoke in the hallway.”

The Fire Department said this was a kitchen fire and it was contained to that one unit.

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There was no adult inside the apartment at the time of the fire. The mother of the children was nearby.