The Police Service of Northern Ireland is to investigate claims a man found dead in Ibiza was beaten while in police custody.
Alan Drennan, 21, from Newtownabbey in County Antrim, headed off on holiday with 10 friends from Belfast on Saturday.
He reportedly told friends he had been beaten up by Spanish police while being questioned in the airport moments after landing.
He allegedly had a cut on his head and arm, and also said he had bruising to his back.
He was found dead in his hotel room on Sunday after a night out, and Spanish police said they believed he had died of natural causes, saying there was no signs of injury.
PSNI Detective Superintendent Kevin Geddes confirmed that an investigation had been opened into Alan's death, telling the Belfast Telegraph: "We plan to speak to any potential witnesses and gather any relevant information in order to assist Spanish police."
Alan had been sitting separately from his friends on the flight and a complaint had been made about him calling out to them.
He was escorted off the plane by staff, before being questioned by Spanish police.
A source told the Mirror: "Information is slowly coming out about the situation in Ibiza and how the Spanish police dealt with Alan both while he was alive and after he died, and it's not good.
"Nothing is going to bring him back but if something was done to him, if he had a fall, if he was hit or injured in any way, then we need to know."
Alan's father, Alan Drennan Snr, described his son as "fantastic", adding: "He was just a super wee lad. He was straight as a die, everybody loved him."
Speaking to the BBC, he said his son and his girlfriend had made arrangements to move to Australia to "start a new life" on his return from Ibiza.
Alan's friends returned from the holiday and hundreds of people have raised over £10,000 to get his body home and pay for the funeral.
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