Published Tuesday, 27 May 2014
Drugs are thought to have played a role in Oisin's death. (© UTV)
Oisin Crawford died in the border village of St Johnston in the early hours of Monday morning.
The 22-year-old had been partying with friends in a house in the village before becoming unwell.
Four others, including a woman aged 18, were taken to hospital with one man said to be in a seriously ill condition.
Gardaí are investigating a possible drugs link.
Following the death, the Republic's Health Service Executive issued a statement warning people to stay away from illegal drugs.
The statement mentions an ecstasy-like substance sometimes referred to as "Double Cross" or "Double Black", and health officials are warning of the potential dangers linked to these substances or of using drugs in combination.
A drugs awareness group in Derry is also warning anyone feeling unwell after using illegal drugs to get immediate medical attention.
Ian Callaghan from the Divert Project said the only guarantee of safety was not to take any illegal drug.
He added: "You can't mess about with drugs like this.
"If you wait and ignore the symptoms then you can get yourself in great difficulty and potentially a fatality could occur."
© UTV News