A care assistant at a secure unit in north Suffolk who was having a relationship with a mentally-ill prisoner she helped to escape has been jailed for 18 months.

Rebecca Martin, 22, was waiting in her car in the car park of St John's House, in Palgrave, near Diss, in the early hours of the morning when Luke Sparks overpowered a member of staff and used a fire extinguisher to smash his way out of the building, Ipswich Crown Court was told.

Martin and 21-year-old Sparks had then driven to the Bristol area where they were arrested two days later.

Martin, of Greys Manor, Banham, admitted assisting Sparks to escape on October 2 last year.

Sentencing her, Judge Rupert Overbury described her as 'naive' and said she had thought she was in love with Sparks and that he was in love with her. He said she was guilty of a serious breach of trust and had potentially endangered the lives of other people by helping Sparks to escape.

Sparks, 21, of Weston-Super-Mare admitted escape from custody and was jailed for 30 months while another prisoner, Jason Williams, 21, who admitted escape was given a nine-month prison sentence suspended for two years.

Rex Bryan, prosecuting, said Sparks was placed at St John's House in December 2009 for robbing and stabbing a taxi driver. The apparent trigger for the break-out by Sparks was a decision by a tribunal a few days earlier not to recommend his release.

Mr Bryan said Martin would have known it was 'entirely inappropriate' for her to have a relationship with Sparks.

On the night of the escape, Sparks went to an office and demanded keys from a member of staff. The man was punched and suffered burn injuries to his arms and back after a fire extinguisher was sprayed on him.

The court heard that Williams had not been part of the planned escape but had joined in after Sparks had got the keys from the member of staff. He was arrested several hours later as he was cycling back to the unit.