A 19-year-old British man is reportedly missing in a mountain region of Tenerife.
Jay Slater, from Oswaldtwistle in Lancashire, was last heard from at around 8:00 BST on Monday.
His friend Lucy said he had called her to say he was lost, needed a drink of water and had 1% battery on his phone.
Mr Slater’s phone then cut off, with his last known location showing as the mountainous Rural de Teno national park in the north west of the island.
He has not been heard from since.
Lucy, who travelled to the island with Mr Slater to attend the NRG music festival, said he had gone to stay with some people he had met on the holiday.
However she said Mr Slater seemingly did not realise how far away they were from where he was staying, and set out on Monday morning to walk home.
She told the BBC she had spent "all day up this mountain" looking for him, and was about to head out to resume the search.
Mr Slater’s mother was said to be on her way to Tenerife and the British Embassy had been informed.
A spokesperson for the Foreign Office told the BBC: "We are supporting the family of a British man who has been reported missing in Spain and are in contact with the local authorities."