Australian authorities said Thursday that they were investigating videos a U.S. influencer posted online that show him capturing and restraining wild crocodiles in the state of Queensland.

“These actions are extremely dangerous and illegal, and we are actively exploring strong compliance action including fines to deter any person from this type of behavior,” the Queensland environment department said in a statement.

Mike Holston, also known as The Real Tarzann, posted two videos in recent days to his 15 million followers on Instagram, including one in which he appears to wrestle a crocodile and ends up on top.

In the first video, Holston enters shallow water from a boat and runs toward what he says is a freshwater crocodile before he jumps on it and wrestles with it. Blood is visible on his left arm as he grabs the neck of the crocodile, which can be heard calling out.

“This is what dreams are made of,” Holston says in the video as he holds the reptile, admitting that he has wanted to go to Australia since he was young to see crocodiles up close.

Since it was posted Friday, the video has garnered over a million likes and been viewed more than 33 million times.

In the second video, Holston is seen in marshland chasing after what he says is a juvenile saltwater crocodile. He grabs the reptile rather easily, which Queensland officials said was “completely uncharacteristic,” citing crocodile experts.

“In normal conditions, such an animal would writhe and thrash about wildly, seeking to escape,” they said.

Both animals can be seen being released in the videos, which appear to have been recorded at Lockhart River on the Cape York Peninsula.

Holston did not immediately respond to a request for comment Thursday.

In a comment on the video of the saltwater crocodile, he said he did not encourage anyone to try to re-create what he was doing, adding that the animal was “released after a few close looks and photos were taken.”

Not everyone, however, is buying that explanation.

Conservationist Bob Irwin, father of the late Steve Irwin, Australia’s famous “Crocodile Hunter,” called for greater penalties for social media posts such as Holston’s.

“People visiting our country need to respect our wildlife, or they need to be booted out the door,” Irwin said in a statement that appeared in Australian media.

Jeff Corwin, an American wildlife biologist and conservationist, said Australia has strict regulations when it comes to its animals.

“Australia has faced incredible conservation challenges, from invasive species and habitat loss and a very rapidly changing climate, so they have all hands on deck to protect wildlife,” he said in an interview. “And a lot of people may be surprised to discover that top on their list for protecting are the reptiles.”

Encounters like Holston’s can be dangerous for both the person and the crocodile, Corwin said.

“These are powerful predators, incredibly cunning. So if you’re not being careful, you could be injured, and people have been killed trying to work or hands-on connect with these animals,” he said.

In addition, “if you’re reckless, if you don’t know what you’re doing and you’re being negligent or manhandling that crocodile, you could severely injure that crocodile,” Corwin said. “Yes, they’re tough, and they’re time-tested — they’ve been on our Earth for 60 million years — but they are sensitive creatures.”

Both saltwater and freshwater crocodiles can range from about 6 to 13 feet long, with male saltwaters weighing as much as 660 pounds and male freshwaters weighing as much as 132 pounds, according to the Queensland environment department.

The maximum penalty for interfering with a crocodile is a fine of about 37,500 Australian dollars ($25,000).

Holston is not the first U.S. influencer to have had a run-in with Australian authorities over wildlife content. In March, a self-described “outdoor enthusiast” left the country after she was widely criticized for recording herself snatching a baby wombat from its distraught mother, including by the Australian prime minister.