A stalker from Earlsfield threatened presenters at Radio Jackie in a five-month campaign of phone calls, emails and texts after she became fixated with the station.

The broadcaster had to beef up security at its Tolworth Broadway premises after Alida O’Reilly, of Earlsfield Road, became obsessive, Kingston Magistrates’ Court heard.

The court was told she first called the station in July 2009 to ask for Billy Idol or Michael Jackson songs to be played on its Juke Box show, but became “frustrated and vaguely aggressive” when presenters stopped doing what she wanted.

Presenter and station manager Steve Mowbray said: “I remember one email saying ‘I hope you like Michael Jackson because you are going to meet him soon’. This would have been a few days after he died.”

Mr Mowbray said he felt she had taken control of his life and some presenters did not want to do shows or open emails.

He said: “She was emailing telling us she was going to commit suicide. She told us what pills she had and what she was going to do.”

Magistrates heard on April 19 she branded another presenter, Dave Owen, a “racist lunatic who should be sectioned forever” in an email. She posted offensive allegations on an American website, including details of his workplace, hours and a photograph.

The court heard she threatened presenters with her “Irish friends” in texts, and used Facebook to warn “what goes around comes around”.

Mr Owen told the court she had contacted him hundreds of times, and said: “She was obsessive in whatever she was saying. First it was ‘I love Radio Jackie’. Then it was ‘I hate Radio Jackie’ or ‘I hate you’.”

Mr Owen said she stood staring at him just 2ft away while he did a broadcast from a Kingston shop on November 12.

He said: “I said ‘Alida, do you mind moving back’. She became verbally abusive. Then she started prodding me with her finger.”

Police arrested Ms O’Reilly on November 19 after she had been staring at Radio Jackie presenters covering the Christmas lights switch on.

The court heard Ms O’Reilly, 27, was not fit to enter a plea during Monday’s trial. Magistrates, who were unable to convict her of two counts of harassment under mental heath legislation, found she had harassed Mr Mowbray and Mr Owen, and adjourned the case until May 19 for a second doctor’s report.