An escaped prisoner who had been on the run for 17 years has been arrested in China after a drone spotted him living in a secret cave.

Song Jiang, 63, escaped from a prison camp in 2002 after being jailed for trafficking women and children.

Police spent years searching for the fugitive, but were unable to find him until a drone discovered clues in the mountains behind his hometown in the country's Yunnan province.

The key giveaway was a blue piece of steel peeking out from the leafy forest, police said.


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Upon closer inspection, police found the steel was covering a cave surrounded by bits of human garbage. Officers then hiked for more than an hour through the dense vegetation and found Song hiding inside.

Song was grey-haired, dishevelled, and unable to communicate after years of isolation when officers found him, according to Yongshan police.

His cave was about two square metres wide, with steps out the front and a makeshift bed inside.

Song told police he had survived by collecting water in plastic bottles from a nearby stream.

He then confessed to escaping from prison and was taken back to jail.