Police have outlined the risks of illegal raves after a 26-year-old woman was left in a critical condition after collapsing at an unlicensed event on Saturday night.

The woman, from Bury St Edmunds, is believed to have taken a cocktail of drugs and alcohol at the event held in remote woodland near Croxton.

Between 200 and 300 people were in attendance, with most dispersing once the woman had collapsed just before 9am on Sunday morning.

Chief Supt Nick Davison, Norfolk policing commander, condemned the rave, saying the case highlighted the inherent risks associated with unlicensed events.

'The reality of this incident is a sobering one and people attending these events need to consider whether it is really worth the risk.

'The woman was critically ill, ultimately requiring the services of the air ambulance to get to hospital as soon as possible. The very nature of these events mean they are held in remote locations and people attending are unnecessarily gambling with their own safety.

'In the interests of public safety and to minimise the impact these events have on our local communities, we will continue to do what we can to deter and disrupt these events and to seek to prosecute organisers,' he said.

Emergency services were first alerted to the rave at around midnight, after police received reports of loud music being played at a location near Fire Ride 62, off the Wretham Road in Croxton.

Officers worked with party-goers to close down the event as soon as was safely possible. As they worked, police were told a woman had collapsed just before 9am.

An ambulance with paramedics from Thetford attended, but due to the patient's critical condition, the East Anglian Air Ambulance was called.

Such was the severity of the woman's condition, paramedics were forced to render her unconscious before she was airlifted to West Suffolk Hospital.

Gary Sanderson, communications manager for the East of England Ambulance Service, said: 'Incidents such as this highlight the dangers of taking drugs and the effect it could have on the patient and her family.'

Police have since released dramatic video footage of the air ambulance taking the woman away.

A variety of equipment, including speakers, mixing decks and a generator, were seized at the event and inquiries are continuing.

Police said the call-out came on one of its busiest weekends of the year, with calls increasing 10pc year on year.

The police control room received 3,247 calls during Friday, Saturday and Sunday, compared to 3,079 for the same period last year. One in four was a 999 call. Norfolk police was unwilling to blame the increase on the heat, but said the period had seen some days receive more than 1,300 calls – the same amount usually received on New Year's Eve.

To view the video footage of the incident, go to www.edp24.co.uk