A 19-year-old man from Portobello collapsed and died Saturday in the main area of the event in Dores, Scotland, the BBC reported Sunday.
"Early indications are that the man may have consumed drugs and this is one of the lines of inquiry at this stage," said a police spokesman, whose name was not reported.
A 19-year-old woman and a 20-year-old man were also treated after they allegedly took "legal high" drugs, the BBC reported. Police said they are investigating the use of a substance known as Benzo Fury, a drug often prescribed through hospitals.
"People may think that 'legal highs' are safe, because they are not classed as a controlled drug, but they are extremely dangerous," said Superintendent Stevie Mackay, the event commander.
"If anyone has the tablets described or any other drug, whether controlled or a 'legal high', in their possession, they are advised not to take them and to hand these in."
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