The fires have been on farmland in areas around Newton Abbot, Teignmouth, Paignton and Dawlish.
All the incidents involved a number of fire crews attending the scenes for long periods of time.
Safety advice has now been issued to farmers on how to reduce the risk of arson, including preventing easy access and installing security.
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No one was hurt
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'Progress is moving fast'
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Police would like to identify man
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Cllr Andrew Mitchell made his feelings known
Torbay's bigger buses outgrow streets
'Operating buses of this size on those roads would create safety and reliability issues'
Anger at plans for 700 homes in Exmouth
They're unhappy about proximity to heath
