There is still one big question about Jay Slater’s disappearance that Tenerife police haven’t answered.

The 19-year-old was on holiday in the Canary Islands with friends, attending a music festival, when he went missing on June 17.

The bricklaying apprentice from Lancashire was facing an 11-hour walk, having missed the bus back to where he was staying, from an Airbnb being rented by two strangers.

With the remaining one percent of battery on his phone, he called one of the friends he was on holiday with to say he was lost, thirsty and injured.

No one has heard from him since and search parties have been scouring Rural de Teno Park, an area popular with hikers thought to be his last known location based on the last data provided by his phone before the battery died.

Jay had been attending the NRG music festival when he was seen getting into a car with two British men he met earlier in the night. He stayed overnight in their Airbnb in Masca.

Little is known about the men, who have not spoken publicly, besides the fact they are British, black and in their late 30s to early 40s.

Witnesses say they were seen drinking Hennessey in bars and nightclubs in the party resort of Playa de las Americas during the NRG festival. They reportedly did not attend the festival.

Investigators have spoken to the pair and they are “not in any way relevant to the case”. They were only in Tenerife for a couple of days before travelling back to Luton Airport.

One big question that remains publicly unanswered by Tenerife police is why Jay went back to the men’s Airbnb.

Former detective Mark Williams-Thomas has described the men as “key witnesses”. There is no suggestion that either is responsible for any wrongdoing.

He said: “I need to speak to those people because they are the last people, other than the owner of the holiday rental, that saw Jay.

“I believe they have crucial information that may enable us to find out what has happened to Jay. They were in the bars of the strip area, certainly, for two days, they mixed with Jay and Jay’s group of friends that were there.

“There will be many people asking very pertinent questions into why were they here, what were they doing, why did they take Jay back to that holiday rental?”

Police in Tenerife have ended their two-week-long search near the mountain village of Masca for missing Jay, which has involved sniffer dogs, a helicopter and mountain rescue experts.

A Guardia Civil spokesman said: “The search operation has now finished, although the case remains open.”

Tenerife police have been contacted for comment.