The detective 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.
“They spent a number of time in the bars there, they say that they drank Hennessy, which was their preferred drink.
“I know the nickname of one of those individuals. I have a photograph of that individual. He’s about six foot tall, he’s quite stocky, he had a distinctive bright orange wristband on and he’s got quite short black hair. It’s very difficult to tell, but I think he’s probably aged around 30 to 40.
“One was a slightly bigger guy and was much more chatty than the other person.”
Giving more details about the two men, Mr Williams-Thomas said: “They didn’t go to the festival – they didn’t have tickets.
“There will be you, as well as many other people, asking very pertinent questions into why were they here, what were they doing, why did they take Jay back to that holiday rental?”
Asked what he thought to Spanish police allowing the two men to leave the island, he said: “I think the problem is the starting point of the investigation for the Spanish authorities has been one of a missing person.
“If this was in the UK I would have started investigating as a critical incident and I’d have done everything so that you can secure the potential crime scene. Once you’ve lost evidence you’ve lost evidence.”
Mr Williams-Thomas added: “One of the early thoughts of the family was that Jay was being held hostage. There have been no requests for financial remuneration in any aspect at all.