Police believe the deaths of three men in Suffolk are linked to a "dangerous batch of drugs" which appeared in the Netherlands last month.
The pills, believed to be red and triangular with an "S" Superman emblem, had a large concentration of PMMA, which acts more slowly than MDMA.
This can encourage people to take more pills as they do not think it is having an effect.
PMMA can cause a high body temperature and an increased heart rate.
A spokesman for Suffolk Police said this is the first time they have come across pills matching this description.
Police investigating the deaths of three people believe they took a drug described as a red triangle shape with a superman sign on it.
Officers are appealing to anyone who has been offered the drugs, believed to a "dangerous batch" of ecstasy, to contact police.
Police have urged anyone who has been recently offered ecstasy in the Ipswich area to come forward following the deaths of two people.
Suffolk Police said the deaths of the two men on New Year's Day and another man on Christmas Eve could be linked to a "dangerous batch of drugs".
As well as it being illegal to sell and buy drugs, it can also be very dangerous as we have sadly seen with these tragic deaths.
We would urge everyone not to be tempted to take illegal drugs, you don't know where they have come from, what they are made up of, or how your body will react to them.
If you have been offered drugs in the Ipswich area over the past few weeks, in particular ecstasy, we'd urge you to contact us with any information so that we can find those responsible and remove these dangerous drugs from the streets.
Two people have died and a third is in hospital as a result of what police believe could be a "dangerous batch of drugs".
Two people have died and one is in hospital as a possible result of dangerous illegal drugs. Any info call 101. http://t.co/qLS8O7LYAk
Suffolk Police were called to Rendlesham at 7.10am following peports that a man in his 20s was unwell. He was treated by the emergency services, but was later pronounced dead at the scene.
Police then called to an address in Ipswich at 9.40am after two more men were reported to be unwell. One man, also believed to be in his 20s, was pronounced dead at the scene.
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A pair of 100-year-old biscuits, which were issued to soldiers during the First World War, are to go under the hammer at Lockdales auctioneers in Martlesham, Suffolk.
The snacks have been preserved for nearly a century after being brought home by front line survivor Lieutenant Lionel Bruce Charles, who served with the 5th Battalion of the Queen's Regiment in Gallipoli and the Dardanelles in Turkey.
The bidding for the biscuits which have survived some of the bloodiest battles of the First World War will start at a modest £60.
Each of the biscuits have a label on them saying: "Biscuits used by troops in Sulva Bay" - the peninsula captured by British soldiers at Gallipoli in 1915.
"This 100th anniversary year since the start of The Great War makes all memorabilia from the period collectable," auction manager James Sadler said.