AN INMATE at Greenock jail who had been issued with a Scottish Prison Service mobile phone was caught using an unauthorised sim card in the device.

Christopher Gillen - a remand prisoner - had tried to hide the prohibited microchip from guards but it was discovered during a random spot check of his cell.

A sheriff court sentencing hearing was told that Gillen, 36, was using the illicit sim to keep in touch with family because he had 'run out of credit' on his official one.

A Crown prosecutor told the hearing: "At around 11am, prison officers were conducting cell security checks within HMP Greenock and attended the accused's single-occupancy room.

"After officers entered his cell, Gillen immediately lunged towards the bed area and picked up a mobile phone and attempted to conceal it.

"Officers convinced him to hand over the phone."

Gillen, who according to his lawyer was eventually acquitted on the matters he had been temporarily locked up for, committed the offence on February 3 last year.

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Solicitor Gerry Keenan said: "The sole purpose of the exercise [having the sim card] was to discuss matters with his family because he had run out of credit with the device provided."

Mr Keenan said his client is currently subject to a two-year community payback order imposed at Ayr Sheriff Court.

Sheriff James Varney told the lawyer that Gillen had been 'taking advantage' of the system by using the item which other prisoners did not have access to.

As a direct alternative to a custodial term, Gillen, of Galloway Avenue in Ayr, was ordered to complete 120 hours of unpaid work and he will be supervised by criminal justice social workers for 12 months.