The couple's neighbor, Jeff Fisher, tried to intervene in the attack but was stabbed multiple times, as well. He retreated to his home across the street from the couple's on Southeast Kokomo Lane just north of the Jupiter border to call 911. He told dispatchers he was "bleeding profusely."
Harrouff's mother, Mina, also called officials about her son after he walked out on a family dinner at Duffy's Sports Grill and hadn't been seen since. She told Jupiter police her son, a sophomore at Florida State University, had told her he was immortal and had super powers.
As deputies took Harrouff into custody, the Sheriff's Office said he dared deputies to test him for illegal substances.
They are, but complete results for whether Harrouff was under the influence of flakka or bath salts -- which have been linked to violent outbursts -- aren’t yet available.
“I think that will provide a big piece of the unknown is exactly what (was) in the blood of our suspect,” Martin County Sheriff William Snyder said.
Preliminary tests done last week found no traces of street drugs such as marijuana, methamphetamine or cocaine in Harrouff’s system.
The teen may have ingested a chemical in the couple's garage, though, Snyder said Monday, a week after the stabbings.
“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,” Snyder said.
Harrouff remains in critical, but stable, condition at St. Mary’s Medical Center, the Sheriff’s Office said. It plans to charge the 19-year-old with two counts of first-degree murder and one of attempted murder once he is released from the hospital, which doctors anticipate could be as early as this week.
Anyone with information about the attacks is asked to call investigators at 772-220-7060.