Austin Harrouff, a 19-year-old sophomore at Florida State University, was dining at a sports bar in Jupiter, Florida on Monday night with his parents when he reportedly became irate over delayed service and stormed out. The Alpha Delta Phi fraternity brother, who was behaving “erratically” according to a statement made by his parents, then wandered three miles on footbefore randomly turning up the driveway of a couple relaxing in their garage. Moments later, John and Michelle Stevens were viciously stabbed, and Harrouff was found biting off chucks of flesh from the face of the deceased husband.

The horrific scene has shocked and appalled even the most toughened detectives, and the bizarre, demonic behavior by Harrouff is being linked to the synthetic drug Flacca, according to sources.

Flacca - The 'Zombie' drug

The drug, ostensibly named after the hip hop artist Waka Flocka Flame, is a synthetic, designer drug in the cathinone category of psychoactive substances. According to DrugAbuse.gov, synthetic cathinones are also known as “bath salts,” and are “chemically related to cathinone, a stimulant found in the khat plant.”

A growing problem in Florida since 2013, individuals taking Flacca display symptoms such as nervousness, severe agitation, hallucinations and paranoia – and possess an almost superhuman strength.

According to MedicineNet.com, it is “common to hear reports that it takes multiple people to restrain and sedate these patients.” Some call Flacca a “Zombie drug.” It’s cheap and can be taken orally in a pill form.

Harrouff could not be restrained

In Harrouff’s case, three Martin County Sheriff’s deputies attempted to drag the shirtless attacker off of 59-year-old John Stevens.

His 53-year-old wife, also killed in the fatal knife attack, was lying nearby. Multiple Taser shots on Harrouff had no effect, officials said. A neighbor who tried to intervene was also stabbed multiple times by the rampaging teen, and eventually a police K-9 unit responded and the dogand deputies were able to wrestleHarrouff away.

Teen was 'making animal noises'

Sheriff William Snyder said they have yet to determine a motive in the attack – and an explanation may possibly never come. Snyder said the teenager was “grunting and growling,” and “making animal noises” when they eventually subdued him.

“One of the first things we try to do at our Crime scene is begin to understand the motive of the offender,” Snyder said at a News conference on Tuesday. “In this case we can’t establish a motive… We just don’t know what was going on in his mind.”

Harrouff, a former high school football player and wrestler, was studying pre-exercise science at FSU. He had traveled back to South Florida with friends and was visiting his parents, who are separated, at Duffy’s Sports Grill on Indiantown Road.

Something drove the teen mad, and he fumed out. But instead of going to his father’s home nearby, he wandered in the setting sun until he set upon the Stevens, who were relaxing in their garage turned lounge.

Harrouff is currently under sedation at a nearby hospital and is listed to be in a “deteriorating condition.”