After playing soccer, a teen walked down to the beach and put his feet in the ocean. When he took them out, he noticed something stuck to him, so he brushed it away. It started bleeding. When it wouldn’t stop, he was rushed to the hospital. That’s when doctors broke the news.

Sam Kanizay was just 16 years old when he received the shock of his life. The teen went wading at the beach to cool off after finishing a soccer match in Melbourne, Australia, only to leave the water and soon realize that his legs were dripping with blood. Unbelievably, it seemed mysterious sea creatures had tried to eat the boy alive, The Sydney Morning Herald reported.

After only being knee-deep in the ocean at Dendy Street Beach in Brighton, Sam felt something but didn’t think much of it. First, there was some tingly around his toes. Then, as he emerged from the water about 30 minutes later, there was another odd sensation. Initially thinking it was just sand, he shook off his legs and continued on his way. Soon, however, he looked down to see blood everywhere. That’s when he knew something was wrong.

“I wasn’t really thinking about being eaten,” Sam said, recalling the odd sensation he had experienced and ignored. “I walked out of the water, saw what I thought was sand covering my ankles and lower calf so I just shook it off violently and it came off.”

As he went to fetch his belongings, he noticed that blood had begun dripping down his ankles and feet. His legs were bleeding profusely, and it wouldn’t stop. “I didn’t really know what to think of it, it was a bit of a shock. A bit of a random thing to see,” he recalled. And, when you see the graphic images of his injuries in the footage below, “shock” seems to be an understatement.

Unable to stop the bleeding, Jarrod Kanizay rushed his son to the hospital, where doctors were just as baffled about the boy’s condition as Sam and his father were themselves. “My dad gave me this funny stare and I gave him a stare because we both just had no clue what was going on,” Sam said. Eighteen hours later, while still laying in the hospital, Sam’s legs continued to ooze blood, and doctors were stumped as to the cause.

Eventually, it was determined that the teen had suffered multiple bites from tiny sea creatures that were literally trying to eat him alive. However, doctors were perplexed as to the exact culprit. Experts initially believed that it may have been scavenging sea lice, also known as isopods, munching on the teen’s legs while he was wading in the water. However, the theory is a stretch since sea lice usually only leave a tiny rash and don’t normally cause bleeding.

Wanting to get to the bottom of things, Sam’s dad headed to the beach to do his own investigation. Armed with some meat and a pool net, it wasn’t long before he had what he needed. Hordes of critters rushed to devour the meat, allowing Jarrod to take video of the creatures and also capture some of them so he could show the doctors exactly what had done the damage to his son.

According to Alistair Poore, associate professor at the University of New South Wales, what Jarrod captured weren’t sea lice at all. He said they instead looked like amphipods. But, this did little to solve Sam’s mystery since Poore noted that amphipods aren’t known for biting humans, so he doesn’t believe that these were the same creatures that bit Sam.

“You can attract a lot of animals in the sea with raw meat,” Dr. Poore explained. “Even though it’s interesting, it doesn’t prove to me they were the ones that bit his legs.” Although he believes Jarrod captured amphipods with his meat-filled pool net, Poore is still inclined to believe that sea lice caused Sam’s injuries. However, there’s really no way to tell at this point.

Although Sam was expected to make a full recovery, his parents still wanted to come forward with his unusual case, which eventually drew worldwide attention. Although they’d love to have answers as to what really injured their son, there’s more to them sharing their story than just that.

“I’d hate to see anyone else going through this. If we can prevent it for anyone else, that’s the aim of us talking to people,” Jane Kanizay, Sam’s mother, explained while at her son’s hospital bedside as his legs continued to ooze blood days after the incident.

She may have succeeded in her endeavor, even though the culprit hasn’t been identified because plenty of people are going to be hesitant to even go back into the water after seeing this. I think I’ll stick to swimming in a nice, clear pool. Sam, however, is undeterred. “Plenty of people go for a swim in there so it’s probably just a one-off thing,” he said, relaying that the incident won’t keep him out of the water.