CHICAGO (STMW) — A blocked furnace may be to blame for a carbon monoxide leak in a Northwest Side Logan Square home that sent seven people to area hospitals Tuesday night.

Emergency crews called five ambulances to the home in the 2600 block of North Springfield Avenue about 7:50 p.m. and found high levels of carbon monoxide in the home, authorities said.

Crews found 300 parts per million of the gas in the home, which can be fatal over a short period of time at that level, Fire Media Affairs spokesman Larry Langford said.

Seven people were taken to Norwegian-American Hospital and Saints Mary and Elizabeth Medical Center, all in good condition, according to fire officials.

A furnace in the residence had a blockage and was leaking the gas, Langford said.

People’s Gas crews shut off the heater, and is in the process of ventilating the building and checking other units as of Tuesday night, utility spokesperson Kathy Hartman said.

(Source: Sun-Times Media Wire © Chicago Sun-Times 2013. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)

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