So-called 'speckled Rolex' ecstasy tablets have been linked to the sudden death of a man in west Belfast.
Police have said one man was pronounced dead at the scene in the Thornhill Court area of Twinbrook at around 7.40pm last night.
Four other people were taken to hospital where their condition was said to be stable.
The death has been linked to yellow ecstasy tablets known as 'speckled Rolex'.
The age of the dead man or the other victims are not yet known.
A post-mortem is due to be carried out on the deceased, police said last night.
They have also appealed for anyone in possession of the pills to dispose of them immediately.
SDLP councillor Brian Heading has said the death of the young man was "tragic".
"The tragic loss of life of a man in Twinbrook yesterday evening will be a devastating blow to his family and friends particularly at this time of the year," he said.
"My thoughts and prayers are with them at this very difficult time.
"They are also with the four people who have been hospitalised and I hope that they make a full recovery."
Earlier this year two sudden deaths of people – one in Belfast and one in Coleraine – were linked to another type of ecstasy tablet known as 'green Rolex'.
The pills get their name because of a crown logo stamped on them similar to that of the famous watchmaker and jeweller.
Detective Inspector Andy Dunlop of the PSNI's Organised Crime Branch said at the time of the earlier deaths this year that "despite previous warnings by police and continued uncertainty surrounding the causes of a number of recent unexplained deaths, people are continuing to put their lives at risk".
"The combination of MDMA (ecstasy) and PMA can be particularly hazardous to health and has been linked with numerous deaths worldwide," he added.