LEEDS Festival organisers have issued a warning to festival-goers after revellers fell ill from what is thought to be contaminated Ketamine.
At least two people are understood to have sought medical help after taking the drug.
A tweet on the official festival Twitter feed said: “Beware! There is contaminated ketamine on site. Do not bring, take or buy any drugs on site. Be safe and enjoy the great line up!”
West Yorkshire Police said five men, aged 18 to 25, have already been arrested on suspicion of drugs offences.
Four were held on suspicion of possession with intent to supply class B drugs. The fifth was arrested on suspicion of possessing class B drugs.
A police spokesman issued a warning to would-be drug users. He said: “Security checks on your way into the site will be stringent and staff are adept at finding drug stashes.
“The law at Leeds Festival has to be enforced, just as it would be any other part of the country.
“Anyone found with a suspicious substance will be arrested and taken from the site while tests are undertaken to ascertain the exact nature of a powder or tablet.
“Please also be aware of so-called ‘legal highs’. Despite the name this is no guarantee that it’s safe to take or is in fact a legal substance.
“Whether it’s claimed to be a legal high or a banned substance, people supplying drugs are more often than not unscrupulous individuals who don’t care about you.”