Dogs have been spotted scouring the mountains of north west Tenerife as the major efforts to find missing teenager Jay Slater continue.

The 19-year-old was reported missing on June 17 after he vanished in the Rural de Teno park area, near Masca. He is said to have walked off from an Airbnb he had stayed at the night before his disappearance.

It’s thought he had stayed with two men he met after partying at the NRG music rave in the south of the island.

READ MORE:Jay Slater: Police 'keeping open mind' as rescue teams 'expand immense mountain search area'

On Tuesday (June 25) the efforts to find him intensified even further, with the 30km search area widened to cover the Buenavista del Norte municipality and specialist sniffer dogs flown in from Madrid.

The Canine Unit was flown in from Madrid
The Canine Unit was flown in from Madrid

Pictures from the search base, around half a mile north of Masca and close to where Jay’s phone is said to have ‘pinged’ the morning he vanished, show canine units being drafted in.

The dogs scaled steep parts of the landscape, with efforts particularly focused around the open area where Jay’s last location was picked up at 8:50am on June 17.

Rescue teams are continuing their search

The open space was also the hub of further searches last week, as Civil Guard and Civil Defence officers were seen probing a small derelict hut within the mountains.

Search teams had been focusing on the Masca Gorge near to the spot where Jay phoned friend Lucy on Monday, telling her he was lost with no water and had just one per cent battery on his phone.

Civil Guard officers have now confirmed that forest trails and tracks north of the gorge in Teno Rural Park are also now being looked at as the ongoing search was expanded to other areas.

The vast search area was described by local media as being over 250,000 acres of volcanic landscape, with terrifying 600 metre ravines and gorges.

Local media Canarian Weekly said: “It's important that people remember that the area they are searching is over 250,000 acres of volcanic landscape with valleys and ravines up to 600 metres deep, that is difficult to cross in usual circumstances, never mind when searching for a missing person and not wanting to leave any rock, cave, or bush not searched.”

Buenavista del Norte is the name of the municipality the tiny village of Masca forms part of. It is the town on the north west coast of Tenerife where Jay stopped a local to ask her about bus times.