Suspect in stabbing, face biting case may have ingested chemical from garage, sheriff says

Investigators are trying to determine whether a 19-year-old Florida man could have ingested a chemical from the garage of a couple he's accused of fatally stabbing, according to Martin County's sheriff.

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William Snyder said investigators are continuing to wait for toxicology results for Austin Harrouff, who continues to be listed in stable but critical condition at St. Mary's Medical Center. He has been at the hospital since he was taken into custody shortly after the deaths of John Stevens and Michelle Mishcon late Monday at their home just north of the Jupiter border.

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"It's a typical garage, so there were solvents," he said. "There were things he could have consumed and that first night at the hospital, the hospital speculated based on what they were seeing in his body fluids, that perhaps he had ingested something caustic from the garage."

The FBI is running tests to see whether the Florida State University sophomore was under the influence of either bath salts or flakka — which have been linked to violent outbursts — at the time of the attacks.

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"I think that will provide a big piece of the unknown is exactly what (was) in the blood of our suspect," Snyder said.

Tests done last week found no traces of street drugs such as marijuana, methamphetamine or cocaine.

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The Martin County Sheriff's Office plans to charge Harrouff with two counts of first-degree murder and one of attempted murder as soon as he is released from St. Mary's. Doctors have said that release could come as soon as this week.