An Australian boy had his legs and feet ravaged by “little mite-type bugs” when he went for a swim near his home, his family says.

When Sam Kanizay, 16, of Melbourne got home after taking a dip in the water at Melbourne’s Brighton Beach on Saturday, his legs bled profusely, gruesome photos show.

“It looked like a war injury … like a grenade attack. It was really bloody,” the teen’s father, Jarrod Kanizay, told the BBC.

“We got him in the shower but as soon as we did that, the blood kept reappearing,” his father said. “It wasn’t clotting at all. It just kept bleeding and bleeding.”

Sam stood waist-deep in the bay for about a half-hour to soak his legs after playing a ball game, the BBC reported.

When doctors at two hospitals were stumped by the cause of Sam’s injuries, Jarrod decided to head back to the water to investigate himself.

“I collected these strange creatures from the same spot last night by trapping them in a net and standing in the water myself,” Jarrod told the news outlet.

He poured some water from the part of the bay where Sam was attacked onto some meat in a tank and filmed the experiment — which showed sea lice devouring the meat, the Herald Sun of Melbourne reported.

Museums Victoria scientists identified the creatures as lysianassid amphipods, a type of scavenging crustacean commonly known as “sea fleas,” the paper reported.

“It’s possible he disturbed a feeding group but they are generally not out there waiting to attack like piranhas,” Marine biologist Genefor Walker-Smith told the paper.

The nasty creatures may have possessed anticoagulant-like leeches, which may explain why doctors struggled to stem the bleeding, Walker-Smith said.

Richard Reina, an associate professor at Monash University’s School of Biological Sciences, said he’s never seen “anything like this on a human before.”

“Sea lice normally go after dead or dying animals — they bite humans too but not as severe as this case,” Reina said. “I suspect the reason why the wounds were so intense was because he was standing still for so long and his legs went numb.”

Reina said it was possible Sam was unaware he was being attacked because the water was so cold.

“Normally when you feel a sting, you will naturally move away from the area or get out of the water, but it’s possible he didn’t even know,” he said. “The general public should not be alarmed because this is a very rare case.”

The horrifying experience hasn’t deterred Sam from returning to the bay.

“I may ice my legs in the pool from now on but I’ll definitely go out swimming there again,” he said. “Plenty of people go for a swim in there, so it’s probably just a one-off thing.”