(STMW) — Carbon monoxide poisoning left two men dead and a woman critically injured Thursday afternoon in a home near northwest suburban Des Plaines, according to the Cook County sheriff’s office.

Emergency crews were called to a HazMat situation at a home on the 9400 block of Harrison Street in unincorporated Maine Township about 3:30 p.m. Thursday, according to sheriff’s office spokeswoman Sophia Ansari.

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John Tae Kim, 83; and his son Hong Kyq Kim, 53; who lived in the house, were pronounced dead at the scene, according to the Cook County medical examiner’s office.

A woman identified as the wife of John Tae Kim and mother of Hong Kyq Kim was taken to Advocate Lutheran General Hospital in Park Ridge, where she remained in critical condition Friday, authorities said.

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Autopsies conducted Friday were inconclusive, but Ansari said Friday evening that the men “appeared to have died of carbon monoxide poisoning and their deaths appear to be accidental.”

Four Cook County sheriff’s deputies became ill after entering the home, and were treated as a precaution, Ansari said. They were released from the hospital Thursday evening.

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(Source: Sun-Times Media Wire © Chicago Sun-Times 2015. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)