The family of Justin Plette, the 22-year-old Dutch man whose body was discovered on the rocks at Cresta Quay in St Julian’s on Saturday morning, believe that their son's death was "a robbery gone wrong".

The family and some 20 friends gathered on the site where he was found this evening to hold a memorial and address the Maltese media.

They laid flowers and formed his name with candles. Justin was found at 6.30am on Saturday, fully clothed and in the foetal position facing the sea.

Justin’s father Erik said his son had had one or two drinks at a nearby bar and his friends had last seen him at 1am.

At one point, they left for a few minutes to go to the bathroom and on returning outside, Justin was nowhere to be seen.

Justin, who worked with the Bettson Group, had been living in Malta for the past eight months.

Mr Plette said there was still a big question as to what had led to his son’s death.

The police, he said, were investigating CCTV footage of the establishment where his son was last seen and also of nearby clubs trying to track his movements. The biggest tragedy, he said, was that the CCTV camera right above where he had been found had not been working.

Mr Plette said the family believed that Justin was drugged with a synthetic drug and taken to the club where he was found without his wallet and mobile phone.

He said they were basing this theory on the fact that another person - who they said was either Spanish or Italian, went to a nearby dive centre on Sunday asking if they had found a mobile phone, wallet or identification card as he had woken up without them and he believed that he was drugged.

“Justin was not so lucky, he did not wake up,” his mother Margit said.

The man who went to the dive centre asking about his belongings did not leave his name and neither did he file a police reports. The parents said they were given this information by the centre. Contacted by Times of Malta, a representative for the centre refused to comment.

Asked what were the conclusions of the autopsy held on their son’s body, the parents said they were still waiting to find out. They said they would be taking a blood sample for testing once they were back home to get a second opinion.

Mr Plette said his son had spoken to his parents on Friday at 11pm, a few hours before he went missing, when he told them about a good conversation he had had with boss about his future prospects with the company.

He was excited about the life he was building in Malta, a country he loved and chose to make his second home.

Ms Plette said the family would be taking Justin home to The Netherlands this weekend for burial today week.