(CBS) – Two men died, one woman was critically injured, and four Cook County Sheriff’s police officers were hospitalized Thursday afternoon, after a hazardous materials situation in a townhouse near northwest suburban Des Plaines.

Around 3:30 p.m., a relative of the people who live in the townhouse called 911, and reported finding the victims in distress.

Two men were pronounced dead at the scene, and a woman who was seriously ill was taken to Advocate Lutheran General Hospital in Park Ridge in critical condition, officials said.

Four Cook County Sheriff’s police officers who responded to the scene had to leave the townhouse in the 9400 block of Harrison in Maine Township, near Des Plaines, after they began suffering breathing problems.

“Four sheriff’s police officers who were taken to the hospital have been treated and released. They were released just before 7 o’clock today,” Cook County Sheriff’s spokeswoman Sophia Ansari said.

Within a few hours, emergency crews determined they could take off their hazardous materials suits, and examine the scene freely.

“They were able to rule out anything that was bad, as far as any kind of alkali, or acid that was still in there,” Maine North Fire Protection District Chief Rick Dobrowski said. “They also were able to just test the water that they found, and stuff in there, to make sure that there was nothing that was mixed chemical-wise. So, at this point in time, they also have gas monitors that they found the oxygen levels to be normal.”

It was not immediately clear what type of chemicals or fumes were responsible for the hazardous materials response.

Autopsies on the two men who died – John Tae Kim, 38, and Hong Kyqkim, 53 – were scheduled for Friday.