Dorset Fire and Rescue Service say that arsonists are believed to have started a fire which destroyed heathland on Ham Common in Poole yesterday.
Large fires at Canford Heath and Studland are also thought to be the result of individuals deliberately starting fires.
The service is calling on people to recognise the serious danger posed by the wild fires to people and property.
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Very windy with heavy rain moving east tonight. Becoming drier but staying windy later. Then sunny spells and strong winds tomorrow
Heavy rain and strong winds this evening. The rain will clear tonight but staying windy, especially along the coast
Hampshire police arrest seven more men in investigation into an alleged conspiracy to commit serious sexual offences on the Isle of Wight.