A former BBC radio presenter Alex Belfield found guilty of stalking four people including broadcaster Jeremy Vine has been jailed for five and a half years.
Alex Belfield, who now runs a YouTube channel, stalked his victims by harassing them online.
His trial heard he made YouTube videos about them, posted messages on social media, sent emails, and also encouraged his followers to target them.
The judge said one of his victims came close to killing himself.
Belfield had harassed this victim, BBC Radio Northampton presenter Bernard Spedding, for nine years and some of his followers had sent him death threats.
"He was seconds away from taking his own life as a result of your conduct," the judge, Mr Justice Saini, told Belfield.
"You made this highly successful and confident radio presenter lose all joy in life and turned him into a shell."
Weaponised the internet'
The judge said that while Belfield did not physically approach or watch his victims, the effects were just as damaging.
"The stalking you committed was not the conventional type which is popularised in the press," he said.
"Your methods were, however, just as effective as a way of intimidating your victims, and were in many ways much harder to deal with."
The judge said he agreed with some of the witnesses in the case, who said Belfield had "weaponised the internet".
Belfield, who is 42 and from Nottingham, was originally charged with stalking eight different people, who were mostly current or former BBC staff.
The full wording of the charges stated he "pursued a course of conduct that amounted to harassment" of the complainants, which "amounted to stalking" and caused them "serious alarm or distress".
'Wholly false' allegations
In relation to Jeremy Vine and theatre blogger Philip Dehany, Belfield was found guilty of two lesser offences of "simple" stalking, which does not require serious alarm or distress to be proved.
For each of these offences he was sentenced to 13 weeks, also to run consecutively.
The judge said Belfield had made "wholly false" allegations about Mr Vine stealing £1,000 of BBC licence payers' money, in a video which was viewed by more than 400,000 people.
"You were not a whistleblower in any sense but developed a fixation with pursuing Mr Vine with a campaign of abuse," the judge said.
Belfield also published Mr Vine's address to a "mass audience", the judge said.
"Although you at no stage committed any physical acts, Mr Vine considered himself and his family to be at risk from you and his followers," the judge told Belfield.
"He had to ask his family to watch out for you and to take care in and around their home address."
He was found guilty of this offence in relation to two of the complainants - Mr Spedding, who is known as Bernie Keith, and videographer Ben Hewis.
For each of these charges he was sentenced to two and a half years in prison, to run consecutively.
The judge said Belfield "bombarded" Mr Spedding - who had previously been friends with Belfield - with Facebook messages and emails, and made "highly abusive" YouTube videos containing false allegations.
"He had no escape from you," the judge told Belfield.
The judge said it was an aggravating factor that Belfield's harassment was public, as this caused his social media followers to also abuse Mr Spedding over a "lengthy period".
"In some cases this has extended to death threats," he said.