Austin Harrouff, left, dared arresting officers to test him for drugs after he was allegedly found biting the face of one of his two victims, right.
Police in Florida have revealed that the accused face-biting frat boy Austin Harrouff dared officers to test him for drugs while he was being arrested.
“Test me, you won’t find any drugs," Harrouff said while being dragged away from two fatally stabbed victims in the driveway of their home, a Martin County Sheriff's Office spokesperson said in a statement on Saturday.
The 19-year-old Florida State University student is accused of stabbing to death 59-year-old John Stevens and his 53-year-old wife, Michelle Mishcon, last Monday.
The couple died after Harrouff allegedly attacked them and tried to bite off Stevens' face.
The local authorities also confirmed Saturday that Harrouff is alleged to have bitten Stevens in the abdomen.
The suspect has tested negative for all common street drugs including cocaine, meth and heroin. However, toxiciology tests are not yet complete for lesser known intoxicants known commonly as bath salts and flakka.
Read: Desperate 911 Call Released in Frat Boy Face-Eating Attack: 'I Am Bleeding Profusely'
On Saturday, local officials said they have asked federal authorities to test Harrouff for the other drugs, which have been implicated in violent crimes before--notably in South Florida.
"[The] FBI has agreed to conduct toxicology testing at their Lab in Quantico, VA. The reason for sending it there is the large range of testing that we are requesting and they are one of the foremost experts in the world when it comes to this type of testing," Martin County Sheriff's Office spokeswoman Trisha Kukuva said in a statement.
Harrouff was eating dinner with his family Monday at a restaurant in Jupiter, Florida, before he stormed off at about 8:30 p.m.
According to a police report, his mother, Mina called 911 before midnight Monday, saying: "I don't know how to do this. My son has taken off. It seems like he's a little delusional. He says he feels immortal, like a superhero."
She told the operator that Austin had been "acting strange the last week or so" and claimed he had super powers.
Mina was asked if her 19-year-old son had a drug problem or history of mental illness and she said no.
She said he had no phone and no identification on him when he left the restaurant. Mina added: "I will say the only thing he has on him is a pocketknife switchblade."
Read: Frat Brother Found Eating Face of Victim After Random Fatal Double Stabbing: Cops
The worried mother said she was calling his friends in an attempt to locate her son, but no one had seen him.
The mom's worst fears were realized when cops say he walked four miles before randomly encountering Stevens Mishconin, who were watching TV in their garage.
Harrouff allegedly beat and stabbed the couple to death.
Martin Country Sheriff William Snyder told Inside Edition that the police recovered a switchblade from the sophomore at Florida State University in Tallahassee.
The teen attended Suncoast Community High School where he wrestled and played football.
Harrouff was hospitalized following the attack, but his condition has stabilized. His is now conscious but unable to speak due to a breathing tube. He has not yet been formally charged in the crime.
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