It is understood a man is fighting for his life following a party in Co Donegal at which another man died.

Gardai say they are investigating all of the circumstances surrounding the death of the man (22) in St. Johnston yesterday.

It is believed officers are looking into whether he had taken an ecstacy-type drug.

The alarm was raised at 4:30am yesterday following concerns that five people had become ill at a birthday party.

The Health Service Executive (HSE) says they may have consumed a drug known as "Double Cross" or "Double Black".

It is warning people to stay clear of a new batch of the potentially lethal drugs.