Two men have been arrested by police investigating the deaths of two people who may have taken contaminated ecstasy tablets.
Greater Manchester Police are questioning the men, aged 33 and 34, on suspicion of being concerned in supplying a controlled drug.
It comes after police warned that a contaminated batch of ecstasy tablets could be circulating following the deaths of the two "apparently fit young men" from the same town.
Gareth Ashton, 28, died at Wigan Infirmary on Monday, and Jordan Chambers, 19, died at Oldham Hospital on Sunday.
The pair, both from Wigan, admitted to hospital after complaining of feeling unwell and suffered the same symptoms. Both said they had taken drugs.
Greater Manchester Police are investigating where the men had been socialising and if they were out together when they took the pills.
Several others went to hospital yesterday suffering similar symptoms, but all have been released, said Superintendent Andrea Jones.
A third man, a 26-year-old, died in Liverpool on Sunday and is believed to have taken tablets - possibly ecstasy - before he collapsed.
Greater Manchester Police are not currently linking his death to the two in their region, but said they could not discount a connection.
The drugs thought to be contaminated are brightly coloured heart-shaped ecstasy tablets which come in purple, green, red and yellow. Ms Jones urged anyone with information on such pills to come forward to help them with their inquiries.
Toxicology tests are due to take place to establish how Mr Ashton and Mr Chambers died.
Ms Jones said: "Both had taken drugs, admitted to taking drugs, prior to being admitted to hospital, and our concern is that in circulation in the Wigan area, there could be these contaminated drugs."
She said Wigan is not thought to have a particular drug problem and that Greater Manchester Police are liaising with other forces.
Members of the public were warned of the risks of taking illegal drugs.
"These illegal drugs nobody knows what poisons they contain, what toxic chemicals they contain," added Ms Jones.
Detective Chief Inspector Howard Millington, from Wigan CID, said he was concerned there could be further deaths if the drugs continue to circulate in the area and urged anyone feeling unwell after taking ecstasy pills to go to hospital for a check-up.
"We are very concerned at how these deaths of two apparently fit young men have occurred," he added.
The 26-year-old who died in Liverpool is not thought to be from the Merseyside area.
Detective Superintendent Tim Keelan, of Merseyside Police, said: "The implication that this may be drug related is just one of the lines of inquiry that our comprehensive investigation is looking at.
"This death follows a number of possible ecstasy-related fatalities around the country and while it is too early to link this tragedy with any other incidents, Merseyside Police take this opportunity to warn people of the dangers of taking any illegal substances."
Anyone with information can phone police on 0161 856 7149 or Crimestoppers anonymously on 0800 555 111.