LE PECQ, France (AP) — The vehicle's headlights silhouetted the exhausted teenager walking alone in the rain in deepest rural France, with a skateboard tucked under his arm.

“I said to myself, ‘That’s strange. It’s 3 am in the morning, it’s raining, he’s all by himself on the road between two villages," delivery driver Fabien Accidini recounted.

From there, the story gets stranger still. The youngster, it turned out, was Alex Batty, a 17-year-old from Britain who had been missing since 2017.

British and French authorities confirmed on Friday that the teenager found by Accidini this week was the boy who vanished at age 11, when his mother and grandfather took him on what was meant to be a two-week family holiday in Spain.

Instead, it turned out to be a six-year odyssey through Morocco, Spain and southwest France, living an off-the-grid life.

Until this week. Batty suddenly popped back up on the radar on Wednesday. That's when Accidini found him alone on the remote French road and delivered him to the safe keeping of French police.

The youngster told French investigators that he, his mother and her father had moved from house to house, carrying their own solar panels, growing their own food, living with other families, meditating and contemplating reincarnation and other esoteric subjects.

“It was a nomadic life,” said police officer Lea Chambonniere. “The only constants, the only things they carried with them, were the solar panels and their vegetable plants.”

The teenager decided to put an end to his roaming, parting ways with his mother after she told him she wanted them to move again — to Finland, said French prosecutor Antoine Leroy. He and Chambonniere, a commander in the gendarmerie, spoke at a news conference in the southwestern French city of Toulouse.

“When his mother indicated that she intended to leave for Finland with him, this young man understood that this journey had to stop," the prosecutor said.

He said he couldn't employ the term ‘sect’ to describe how the mother, grandfather and Batty lived. “The term he uses himself is ‘spiritual community,'” he said.

“He was never locked up,” he added. “But he was always obliged to live in these conditions.”

Until he decided to go his own way. Batty walked for four nights — resting during the days — and fed himself with “different things that he found in fields or gardens” before the delivery driver picked him up, the prosecutor said. Batty told police he'd been aiming for Toulouse, hoping authorities there would return him to the United Kingdom to be reunited with his grandmother, who had custody of him before he vanished as a child.

The prosecutor said they'll be reunited in the U.K. this weekend.

“I cannot begin to express my relief and happiness that Alex has been found safe and well," the grandmother, Susan Caruana, said in a statement released by British police.

She said they spoke by video call and “it was so good to hear his voice and see his face again. I can’t wait to see him."

The mother, Melanie Batty, has probably left for Finland, the prosecutor said. The grandfather, David Batty, is thought to have died about six months ago, he said. Both are sought by British police in connection with the youngster's disappearance.

After failing to return to the U.K. from the 2017 trip to Spain, the trio spent about two years in Morocco before traveling back via Spain to southwestern France, where they appear to have spent the last two years roaming in the region of the Pyrenees mountains.

But Batty “does not know exactly where he was, which is very surprising," the prosecutor said. “We will dig a bit."

The delivery driver who found him spotted the teen alone in the rain and dark with a flashlight, a rucksack and his skateboard. He stopped “and asked if he was OK, what he was doing there, if he needed help and if he wanted me to drop him in a village,” Accidini told French broadcaster BFMTV.

Initially, Batty was suspicious, giving a false name, Zac, but he was also “very, very tired,” Accidini said. So he climbed aboard and they got chatting while Accidini finished his deliveries.

“Once he felt reassured, he gave me his real name and told me that he had been kidnapped by his mother five years ago," Accidini said. The teen added "that he’d been in France for the past two years in a spiritual community that was a bit strange with his mother who is also a bit strange, a bit loopy.”

“He’d had enough. He said, ‘I am 17. I need a future.’ He didn’t see a future for him there.”

Batty used Accidini’s mobile phone to send a message to his grandmother. Accidini showed it to BFM.

It read: “Hello grandma it is me Alex i am in France Toulouse i really hope that you receive this message i love you i want to come home.”