A woman has died after falling ill at Creamfields festival.
The 25-year-old from South Wales was taken to Warrington District General Hospital after police were called to the festival in Cheshire at 10.15pm on Friday.
Despite their best efforts, she passed away in the early hours on Tuesday.
Her next of kin have been informed.
Superintendent Sarah Heath, who led the policing operation for Creamfields 2022, said: "The tragic death of a young woman is heart-breaking and our thoughts are with her family and friends at this difficult time.
"An investigation into the cause of her death is underway, but at this stage there is nothing to suggest that there are any suspicious circumstances."
Around 70,000 people were expected to attend the UK's biggest dance festival in Daresbury, near Warrington, over the bank holiday weekend, where acts included Calvin Harris, Fatboy Slim, David Guetta, Becky Hill, Idris Elba and Carl Cox.
Some 39 people were arrested at the festival, Cheshire Police said.
Another 71 were spoken to in relation to the possession of illegal drugs and ejected from the site. They will be dealt with through criminal justice processes at a later stage, the force added.
A further 42 people were dealt with via local resolution and were not arrested but were recorded as being involved in drugs.
A total of 209 crimes were reported for a variety of offences, with 135 of those being drug-related.
The force had urged attendees to leave any drugs and weapons in amnesty bins before entering the festival, warning the actions of those who carry prohibited items could have "life-changing consequences".
Ms Heath said that police made a "conscious effort" to target drug suppliers at the festival.
"This year around 69,000 people attended Creamfields 2022 between Thursday and Monday," she said.
"It's a huge undertaking and we worked with event organisers and security staff in a bid to prevent illegal drugs from getting into the site.
"There were drugs dogs at entrances and opportunities for illegal substances and weapons to be placed in surrender bins along with an extensive search process by security personnel at entrances to the site.
"A conscious effort was made to target those who were intent on supplying illegal substances at the event, which accounted for more than half of the arrests made, while we made use of other options available to us, such as community resolutions, for lower level offences.
"All of those who were arrested and are being investigated for drug offences will now have to face the consequences and pay the price for their actions."