The death of a 24-year-old English woman is being linked to the "party drug" mephedrone.
The woman, who has not been identified, was found by a friend at an address in Norton, north Yorkshire, yesterday.
Detectives believe the woman may have taken mephedrone.
It follows the deaths of Louis Wainwright (18) and Nicholas Smith (19), who died in Scunthorpe last week following a night out.
The incidents prompted criticism of the British government for not doing more to tackle the threat from mephedrone -- also known as M-Cat or Miaow Miaow.
Britain's opposition parties attacked the "inordinate delays" in research into the drug which could have led to it being banned.
It is claimed these delays were related to fall-out from last year's sacking of chairman of the Advisory Council on the Misuse of Drugs, Professor David Nutt.
Ministers vowed that "immediate action" will be taken on a report into a group of so-called legal highs, including mephedrone, due to be issued at the end of the month.
It is expected that British government drug advisers could recommend a ban on the drug within weeks.
After the latest death being linked to mephedrone, North Yorkshire Police issued a stark warning. Chief Insp Nigel Costello said: "Although at this time it cannot be determined whether mephedrone is present within the deceased's system or whether the drug played any part in her death, police would like to warn people about the use of the drug and its potentially lethal consequences."
A post-mortem examination will be held on the woman in the next few days.