Benedict Allen did not want to be rescued.

At least, that's what the British explorer last tweeted on Oct. 11, when he snapped a quick photo of himself heading to the airport on his way to Papua New Guinea.

Allen's goal, he explained on his blog, was to make contact again with the Yaifo, a tribe of people he had first encountered about 30 years ago in the central mountain range of the island country just north of Australia.

“No outsider has made the journey to visit them since the rather perilous journey I made as a young man three decades ago,” Allen wrote. “This would make them the remotest people in Papua New Guinea, and one of the last people on the entire planet who are out-of-contact with our interconnected world.”

Allen, now 57, couldn't resist the allure of trying to reach the Yaifo again to document how their lives may have changed and to see if some of them — including a young girl he had met named “Fifi” — would remember him.

So in October, he flew from London's Heathrow airport to Papua New Guinea, then hired a helicopter to drop him off at an abandoned mission station. From then, he planned to paddle down a river for about a week and try to hike across the rough terrain of the Central Range.

Allen told his fans not to worry if they didn't hear from him until mid-November: He wouldn't be bringing a satellite phone or GPS device with him. He would be going alone. And he had no plan for how he would return to “the Outside World.”

“So, don't bother to call or text!” he wrote. “Because this is how I do my journeys of exploration. I grow older but no wiser, it seems . . . ”

As promised, Allen's social media feeds went dark for more than a month. But when the explorer missed a scheduled flight from Papua New Guinea to Hong Kong this week, Allen's family launched a search effort, according to the BBC.

On Wednesday, Allen's agent, Jo Sarsby, told the news site that Allen had been spotted at an airstrip in the island's Central Range and was “safe, well and healthy.” They planned to evacuate him by helicopter Friday, she said.

“Confirmation on exact location coordinates are now being confirmed in order to arrange evacuation as soon as possible,” Sarsby told the BBC. A call to Sarsby was not immediately returned Thursday.

Allen prides himself on “immersing himself among indigenous peoples” with little more than a handheld video camera — “nothing directed, staged, scripted or subject to 'health and safety' restraints.” He has written 10 books about his adventures and appeared in various television series on the BBC, National Geographic and the History Channel.

Among his accomplishments, he lists making the first known crossing of the Amazon Basin at its wildest and completing the first documented journey of the 1,000-mile Namib Desert in Namibia. In an interview with Lonely Planet published last month, Allen said that one of the lowest moments on his travels was when he had to eat his own dog to survive.

He told the travel site he was trying to avoid certain kinds of dangerous travel now that he was older and had more responsibilities. “I've got three children now, and for that reason I am holding myself back,” Allen said. “I thought I would carry on as normal, but you find yourself not wanting to take certain risks.”

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