A member of the Dartmoor Park Authority has been arrested and bailed by police following the discovery of 189 cannabis plants at a farm in Devon.
69 year old John Shears, from Chagford near Newton Abbot, is a former branch chairman of the National Farmers Union.
Devon and Cornwall Police also arrested three other men on suspicion of production of Class B drugs.
All four men were questioned at Launceston Police Station in Cornwall and are due to answer bail on August 7.
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The long-awaited probe will begin on Monday and is expected to take at least two-and-a-half years.
It comes just days after Take That were also announced as one of several big concerts at the stadium next year.
Mostly dry, plenty of sunshine and warmer