"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.