Peter Hill, 37, of St Andrews Crescent, Rugby, was in custody for an alleged shotgun offence when he told a member of Reliance detention services staff he was going to 'blow her away'.

He also put two fingers to his temples every time Sonia Marsh went past and also threatened to shoot teachers Claire Batchelor and Nicola Rolf, who had made statements about him.

He changed his pleas at a pre-trial hearing, at Warwick Crown Court, to guilty on three charges of making threats to kill.

Prosecutor Tom Schofield told how Hill was arrested on February 19 and kept in custody at Leamington.

When Ms Marsh took him a meal at about 2pm he said: "You'd better get me out of here and sort the matter out."

He later said the offences he was being held for were "only threats" and demanded to be remanded or let go.

Then, in a more menacing exchange, he added: "Come in here, you short-arsed slut, I'm going to blow you away."

In a later outburst he said: "I'm going to **** on you and blow you away, the same as them two teachers."

Mr Schofield pointed out Hill had previous convictions for violence, including robberies, wounding, assaulting a cellmate and affray.

Walter Bealby, defending, said his client had "no recollection of the offences - save to say he was not very well at the time".

He asked for Hill to be sentenced without adjourning for reports to be prepared.

But Judge David McEvoy QC said: "The serious aspect is that this was an inquiry about a shotgun, and it was thought by this individual that he did have one, which caused her to fear she was going to be shot and that the other two were also going to be shot."

He told Hill: "It is important the court is given as much help as possible in determining what is the proper sentence. I am asking for a report dealing with whether you are a dangerous offender."