John Allen Chau is believe to be buried on the beach on North Sentinel Island

Police in India face a difficult task as they attempt to retrieve the body of the 27-year-old American missionary allegedly killed by members of a remote Indian tribe after he attempted to convert them to Christianity.

On Saturday, a team of officers took a boat near the remote North Sentinel Island, which is a part of India, where they spotted the tribe members on the beach close to where authorities believe John Allen Chau was buried.

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Outsiders have long been forbidden by the Indian government from going to the island in order to protect the pre-neolithic tribe’s way of life, and the tribe is known to fiercely repel outsiders.

“The Sentinelese were watchful,” Dependra Pathak, director general of police of the Andaman and Nicobar islands, told the New York Times. “They were patrolling the beach, at the same spot John was killed, with weapons.”

Image zoom John Chau/Instagram

Pathak said the officers sped off to avoid a confrontation with the endangered Sentinelese Tribe, who were armed with bows and arrows.

“Had we approached,” he said, “they would have attacked.”

“This case is the strangest and toughest in my life,” he told the Times. “We are trying to enter into another civilization’s world.”

Image zoom John Chau John Chau/Instagram

The quest to recover Chau’s remains has frustrated Indian police since Chau ventured to the remote North Sentinel Island, was killed by bows and arrows and buried on the beach on Nov. 17.

Since his death, police have sent out teams consisting of coastal guards and officials from the country’s tribal welfare department and forest department to strategize about how to recover his body.

Image zoom John Chau/Instagram

Joining them on their mission have been the fisherman who took Chau to the island and later allegedly watched tribe members drag his body across the beach and bury it in a shallow grave.

Several fishermen and one other man who allegedly helped Chau get on the island are charged with culpable homicide not amounting to murder and with violating rules protecting aboriginal tribes, the Times reports. Other charges are filed against the tribe members in Chau’s death, according to the paper.

“We have mapped the area with the help of these fishermen,” Pathak told the Associated Press. “We have not spotted the body yet but we roughly know the area where he is believed to be buried.”

Any contact with outsiders could prove deadly for tribe members because members may not have the immunity to fight off diseases and illnesses such as the flu.

In 2006, the tribe killed two crab fisherman who washed up on shore. A week after their deaths, their bodies were seen attached to bamboo stakes.

“It was a kind of scarecrow,” Pathak told AFP. “We are studying the 2006 case,” Pathak added. “We are asking anthropologists what they do when they kill an outsider. We are trying to understand the group psychology.”

Pathak told the Times that he didn’t believe the bodies of the two fisherman were ever retrieved and mentioned the same fate might happen to Chau. “If maybe, from a distance, we can see John’s body, then at least his death gets fully established,” he said.

According to journal entries obtained by The Washington Post, Chau first made contact with the Sentinelese people on November 14 and wrote that they allegedly reacted angrily when he tried to preach to them, according to The Post.

“I hollered, ‘My name is John, I love you and Jesus loves you,” Chau explained in his journal on Nov. 16.

Image zoom John Chau/Instagram

The graduate of Oral Roberts University then wrote that one of the tribespeople struck him with an arrow, which pierced through his Bible.

“You guys might think I’m crazy in all this but I think it’s worthwhile to declare Jesus to these people,” Chau wrote before adding, “God, I don’t want to die.”

The following day, Chau ventured back to the island with the help of the local fisherman and tried to make contact again. On November 17, the local fisherman watched as the Sentinelese people dragged Chau’s body away and buried him, CNN reported.