The British journalist and his Indigenous bodyguard were reported missing on Monday after receiving death threats in a remote region of the Brazilian Amazon.

Dom Phillips, 57, a veteran freelance journalist with over 14 years of experience covering Brazil for publications such as The Washington Post, The New York Times, and The Guardian, was last seen on a boat in the Javari Valley over the weekend with Bruno Araujo Pereira, a veteran Indigenous rights protector for Brazil's FUNAI.

Phillips traveled with Pereira, who has received multiple death threats for protecting Indigenous groups against illegal mining, fishing, and forestry. Phillips was writing a book about the environment.

According to a statement from the Union of Indigenous Organizations of Javari Valley and the Observatory for Human Rights for Isolated and Recently Contacted Indigenous Peoples, the two men were last seen riding a boat on the Ituri and Itaqui rivers following a multi-day visit with Indigenous communities.

"It should be noted that Bruno Pereira is an experienced person with a deep knowledge of the region," the two parties said in a joint statement. "The two missing guys were riding on a modern boat with a 40 horsepower engine, 70 liters of gasoline — sufficient for the journey — and seven empty fuel drums.

The pair was anticipated to return to Altalaia do Norte by the river on Sunday morning. A search party was dispatched in the afternoon after they failed to arrive.

"We require an immediate search mission and wed we need the police, the army, the fire department, and the civil defense forces. We have no time to waste, said Beto Marubo, a senior Indigenous leader from the region who is acquainted with the two missing men.

The Guardian stated that it is "extremely concerned and seeking information about Mr. Phillips' whereabouts and condition." We are in contact with the British embassy in Brazil and local and national authorities to quickly uncover the facts."

Former Brazilian President Luiz Inacio Lula da Silva tweeted: "In 2017, I was interviewed by Phillips for The Guardian." I hope they are acceptable, safe, and promptly located."