A man who died while in custody at Dublin Airport had been refused permission to enter the State and was awaiting deportation.

The Garda Ombudsman said efforts to contact the man’s relatives abroad were continuing and no details of the case would be released until this happened.

The man, who was in his 20s, died in Terminal 2 on Saturday afternoon. He had been detained after arriving on a flight into Dublin.

The ombudsman has launched an investigation into the circumstances of the man’s death, as required under Irish and European law. A spokeswoman said the purpose of the investigation was to establish the fact of what happened up the point of the man’s death.

“Investigators are at the scene and a full, independent investigation will be carried out to establish the facts of the situation. Further information will be given when available,” she said.

Given the location of the death, the investigation was likely to make use of CCTV evidence and the testimony of independent witnesses, should these be available, she said.

The man’s death does not appear to be drugs-related, according to sources.

The Garda Press Office confirmed the incident had been referred to the Garda Ombudsman for investigation.