A blaze destroyed 82 cars at the BoomTown festival on Friday afternoon (August 12).
The fire ripped through the West Car Park at the Matterley Bowl near Winchester at around 4.15pm and six pumps and two water carriers were sent to tackle the flames, including the South Central Ambulance Hazardous Area Response Team.
The blaze was brought under control just before 6pm and left the burnt out wrecks of dozens of cars.
There were no reports of any injuries at the scene.
A BoomTown Fair spokesperson said: "BoomTown’ Fair immediately mobilised its onsite fire teams, security and all available staff to the scene.
"Hampshire Fire and Rescue Service, Hazardous Area Response Team (HART) and Hampshire Police, together with the Boomtown Fair staff contained the incident and the fire has now been extinguished. Hampshire Fire and Rescue remain onsite to monitor the affected area."
The Boomtique camp site adjacent to the car park was evacuated as a precaution but all these areas have now been assessed and reopened to the public.
The West Car Park remains closed until an investigation by police and fire services has concluded.
Eyewitness Vikesh Jopanputra said: “I was stood near my tent when I noticed a load of smoke near where many cars were parked.
"I started walking towards it to see what it was, as did many other people, and then that's when I started hearing lots of fuel tanks popping in the distance.
"Every time there was a pop, smoke went up in the air. You could smell the fumes. It was a series of mini explosions. Then the fire engine came through and got it under control."
BoomTown Fair tweeted that an incident information point would be open at West Gate from 12pm-10pm on Saturday, with further support on Sunday (August 14) and Monday (August 15).
A spokesperson said the event management team is working to identify and support festival goers whose cars may have been affected and providing them with internet access and phones.
No festival performances have been affected by the incident and the weekend events are continuing as planned.
Hampshire Constabulary is working with Hampshire Fire and Rescue Service to investigate the cause of the fire.
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