Suspect Randomly Attacked Couple in Face-Biting Murder

TEQUESTA, Fla. -- A 19-year-old Florida State University student with no criminal record fatally stabbed a couple at random in their garage, wounded their neighbor and was biting the dead man's face when deputies finally subdued him, authorities said Tuesday.

Martin County Sheriff William Snyder told reporters that Austin Harrouff may have been on hallucinogenic drugs when he attacked Michelle Mishcon, 53, and John Stevens, 59, at their Tequesta home late Monday.

The sheriff said Harrouff joined his family for dinner at a restaurant a short distance away when he stormed off, apparently agitated about slow service. His parents were so worried by his behavior that they called police and some of his fraternity brothers in a futile attempt to find him before the attack.

RELATED: Suspect Found Biting Man's Face Off At Murder Scene

About 45 minutes later, he apparently targeted the couple at random, the sheriff said.

"It's inexplicable," Snyder said. "One of the first things we try to do at a crime scene is try to understand the motive of the offender, because it is the motive of the offender that gets us going in the right direction. In this case, we can't establish a motive. It's 'I don't know.'"

Snyder said Harrouff stormed out of the nearby Duffy's, a popular sports bar and restaurant, at about 8:30 p.m. He said the would-be rescuer called 911 at 9:20 p.m. to report the attack, which apparently began in the garage where the couple liked to sit at night.

The son of a dentist, Harrouff is muscular -- he wrestled and played football at Suncoast Community High School in nearby Riviera Beach, where rosters listed him at 6-feet-tall and 200 pounds. He's a sophomore at FSU, majoring in exercise science.

When the first deputy arrived minutes later, she used her Taser on Harrouff, but it didn't faze him, he said. She tried pulling him off Stevens' body, but couldn't. Other deputies arrived shortly along with a dog and it took all of them to subdue Harrouff. Snyder said they didn't shoot, fearing their bullets would strike the victim.

"The suspect in this case was abnormally strong," Snyder said, making him think Harrouff was on drugs. He said hospital blood tests showed no signs of methamphetamine, cocaine, heroin or other common drugs; it will take longer to test for less common hallucinogenic drugs such as flakka or bath salts.

"When we see a case like this, when someone is biting off pieces of somebody's face, could it be flakka, the answer is it absolutely could be flakka case, we don't know," said Snyder. "It will be some time before we get any kind of toxicology report, but I would not be surprised, though, if we end up finding out that is the case."

Stevens died in the driveway. Mishcon was found dead in the garage. State records show Stevens recently owned a lawn-fertilizing franchise. The couple was known to hang out in the garage with the door open, reports CBS Miami.

Both victims suffered massive trauma to multiple parts of their body, Snyder said, including stab wounds, slicing wounds and blunt force trauma. Stevens also had "substantial trauma" to his face from bite marks, Snyder said.

Snyder said the neighbor who tried to intervene was stabbed and has been hospitalized, but is expected to survive.

"It was very obvious there was an enormous amount of violence inside that garage," Snyder said.

Dr. Wade Harrouff declined to comment about his son's arrest. The teen is being treated at a hospital.

"Once he got to the hospital he was making animal like sounds and was somewhat incoherent," Snyder told CBS Miami.

Tequesta is a small, affluent community on the Atlantic coast about 20 miles north of Palm Beach.

Flakka had a brief burst in popularity in late 2014 and 2015, primarily in South Florida, but its usage quickly waned after stories circulated about users' deaths and mental breakdowns, and a crackdown was carried out in China, where it has been manufactured.

CBS/AP