A drug charity has told ITV Cymru Wales that one of their biggest battles is fighting against new and unknown drugs.
The message comes after the death of 19-year-old Thomas Jones from Llangefni after he was thought to have taken a drug with the street name "Green Apples" - believed to be a form of ecstasy.
Endaf Evans from charity CAIS says that experts are fighting often against new and unknown substances.
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