Mark's father, Joseph Kiely, told The Portugal News that the family is looking for more information surrounding the death of his son, as there is “no evidence” to support any theory about what happened.

He explained that Mark was actually found on rocks near Albufeira Marina on Monday, 18 August by his own brother after the family flew out to Portugal to search for Mark themselves following his initial disappearance on Saturday, 16 August.

“Mark had been out with his friend in the old town of Albufeira and they were walking back to their accommodation at around 1.30am. They stopped for fast food and then after the tunnel, they became separated. His friend returned to the apartment, where he then slept for 10 hours. When he woke up, he had 4 missed calls from Mark and called him back, but the phone was answered by the police, who explained that his phone and wallet had been handed in.

“We would like to know from the police when he phone was handed in and by who, and where it was found, but we have no information.

“There is a huge question mark hanging over the case”.

Joseph Kiely told The Portugal News that because Mark's body had been there for 3 days, the coroner had to identify him using his dental records as the body had decomposed to a “mass of tissue”.

“There is uncertainty surrounding his death. There is no evidence of a fall, there is no evidence that he was pushed, and there is no evidence of suicide. There is simply no evidence.

“We want to know how he ended up there, after walking for at least 45 minutes and passing many areas where he could have fallen. I just don’t want people to think that this was just the death of a drunken paddy.”

PJ police stated on 21 August that there was no evidence of foul play in the case.

"For now, we don't suspect foul play. It was an unfortunate accident, but we have to wait for the autopsy results," a PJ source told Lusa.

Read more: Police rule out foul play in death of tourist