NEW DELHI (AP) — Indian police have arrested a 24-year-old American Youtuber who visited an off-limits island in the Indian ocean and left an offering of a Diet Coke can and a coconut in an attempt to make contact with an isolated tribe known for attacking intruders.

Mykhailo Viktorovych Polyakov, from Scottsdale, Arizona, was arrested on March 31, two days after he set foot on the restricted territory of North Sentinel Island — part of India’s Andaman and Nicobar Islands — in a bid to meet people from the reclusive Sentinelese tribe, police said.

A local court last week sent Polyakov to a 14-day judicial custody and he is set to appear again in the court on April 17. The charges carry a possible sentence of up to five years in prison and a fine. Indian authorities said they had informed the U.S. Embassy about the case.

Visitors are banned from traveling within 3 miles (5 kilometres) of the island, whose population has been isolated from the rest of the world for thousands of years. The inhabitants use spears and bows and arrows to hunt the animals that roam the small, heavily forested island. Deeply suspicious of outsiders, they attack anyone who lands onto their beaches.

In 2018, an American missionary who landed illegally on the beach was killed by North Sentinel islanders who apparently shot him with arrows and then buried his body on the beach. In 2006, the Sentinelese had killed two fishermen who had accidentally landed on the shore.

Indian officials have limited contacts to rare “gift-giving” encounters, with small teams of officials and scientists leaving coconuts and bananas for the islanders. Indian ships also monitor the waters around the island, trying to ensure outsiders do not go near the Sentinelese, who have repeatedly made clear they want to be left alone.

Police said Polyakov was guided by GPS navigation during his journey and surveyed the island with binoculars before landing. He stayed on the beach for about an hour, blowing a whistle to attract the attention but got no response from the islanders.

He later left a can of Diet Coke and a coconut as an offering, made a video on his camera, and collected some sand samples before returning to his boat.

On his return he was spotted by local fishermen, who informed the authorities and Polyakov was arrested in Port Blair, the capital of Andaman and Nicobar Islands, an archipelago nearly 750 miles (1,207 kilometres) east of India’s mainland. A case was registered against him for violation of Indian laws that prohibit any outsider to interact with the islanders.

Police said Polyakov had conducted detailed research on sea conditions, tides and accessibility to the island before starting his journey.

“He planned meticulously over several days to visit the island and make a contact with the Sentinel tribe,” Senior Police Officer Hargobinder Singh Dhaliwal said.

In a statement, police said Polyakov’s “actions posed a serious threat to the safety and well-being of the Sentinelese people, whose contact with outsiders is strictly prohibited by the law to protect their indigenous way of life.”

An initial investigation revealed Polyakov had made two previous attempts, in October last year and January, to visit the islands, including in an inflatable kayak.

Police said Polyakov was drawn to the island due to his passion for adventure and extreme challenges, and was fascinated by the mystique of the Sentinelese people.

Survival International, a group that protects the rights of Indigenous peoples, said Polyakov’s attempted contact with the tribes of North Sentinel was “reckless and idiotic.”

“This person’s actions not only endangered his own life, they put the lives of the entire Sentinelese tribe at risk,” the group’s director Caroline Pearce said in a statement.