The fire at a Dorset beauty spot tore through heathland and forced the evacuation of a nearby beach.
A huge fire which tore through a popular nature reserve and forced the evacuation of a beach was most likely caused by a barbecue, firefighters say.
At its height on Friday, 90 firefighters tackled the blaze at Studland Heath in Dorset and crews remain at the scene.
Dorset and Wiltshire Fire and Rescue Service said it had discovered a used disposable barbecue amid the ashes.
It has urged people not risk using barbecues in the countryside.
Firefighters had to work in dense smoke which could be seen for miles around. Crews spent Friday afternoon at the scene and worked throughout the night.
Flames leapt across the Isle of Purbeck, forcing police to evacuate Studland beach which had been busy with holiday makers.
Studland Heath is a Site of Special Scientific Interest and home to all six species of native British reptiles including the rare and nationally endangered sand lizard and smooth snake and the rare Dartford Warbler.
A fire service spokeswoman said: “We found evidence of a little camp where someone had used a disposable barbecue, we can’t say 100% that was the cause but when we find evidence we have to assume that’s the most likely cause – fires don’t just start on their own”.
Area manager Jason Moncrief said: “There can’t be many people left in Britain who don’t know the advice at the moment is do not use a disposable barbecue at these places.
“Bring a picnic, use our local cafes, restaurants and takeaways, don’t bring a barbecue.”
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