Today is the fourth day of search and rescue operation for Jay Slater in Tenerife.

He has not been heard from since Monday when he made a concerning call to his friend before the phone cut off.

According to a friend, Slater had missed a bus and said he was going to walk back to their accommodation from the festival. The journey would have taken 11 hours of walking.

The teenager called his friend Lucy on Monday morning to say he was walking back, but his phone was about to die. His last location was Rural de Teno Park, a popular place for hikers.

His mother, Debbie Duncan, said she believes someone may have taken her son. She flew to the island on Tuesday morning to join the search.

"...People must have seen him. And if people haven't seen him, someone must have taken him. It's over 48 hours now since he last had contact with anybody.

"He's out there somewhere or somebody knows where he is. We just need to find my baby."

Duncan says she regrets encouraging him to go on the trip at all.

"I was loving that he was going and saying you'll love it, you'll come back and you'll want to go again."

He was last seen wearing a T-shirt, shorts, and trainers, with a black backpack.

The police, along with the Special Mountain Intervention Rescue Group, have expanded their search to tourist areas near the Rural Teno Park.

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