Sentencing John Larsen to 18 years in prison, Judge Merfyn Hughes said the former mayor had subjected the residents of Denbigh to "a sustained campaign of quite deliberate terror".
He said Larsen's victims were residents of the community he had been elected to serve. Hew said: "Even while detonating these devices, you continued the pretence of showing concern for their welfare and co-operating with the police."
He said Larsen's actions had caused two residents to sell their homes and move away out of fear. He said he was sure someone would have been killed or seriously injured if Larsen hadn't been stopped.
"The jury have seen your evidence for what it is. A dismal attempt to avoid responsibility by one lie after another."
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