Police and drug charities are warning about dangerous double-strength illegal drugs circulating at the Kendal Calling music festival.
The ecstasy tablets are pink in colour with a bit-coin logo on them.
The drug prevention charity The Loop, along with Cumbria Constabulary, has issued an urgent waring to festival goers to avoid taking them.
Analysis has shown that they are up to twice as strong as the average ecstasy tablets and could cause a potential fatal overdose for users.
Anyone who has the drugs at the festival is urged to get rid of them in one of the drug amnesty bins which has been provided.
If anyone has taken the pills and feels unwell, they are urged to seek urgent medical help.