In formal submissions before sentencing, prosecuting barrister Wyn Lloyd Jones said people living on, or close to, Lenten Pool Read, where Larsen set off most of his devices, became "increasingly anxious" as the explosions got bigger.
He said: "It had an impact on sleep. There were concerns about property damage or someone being injured."
He said Larsen used his position of public office to "throw people off the scent", organising meetings to discuss the incidents and reporting explosions to the police, and even gave interviews claiming he was concerned for his family's welfare.
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