The Scottish justice minister has faced fresh resignation calls following the mistaken release of another prisoner.

Security firm Reliance admitted on Tuesday that it had incorrectly released another prisoner.

It was revealed that 20-year-old Joseph Finnan went missing in Hamilton, where he was appearing in court after being arrested for not paying a fine.

After paying, Finnan was then supposed to be taken by Reliance to an appearance at the sheriff court on a separate charge of assault, but was released instead.

The Scottish Prison Service has confirmed that an investigation into the incident has now been launched.

This latest mistaken release follows a number of others over recent months, which have resulted in justice minister Cathy Jamieson halting the roll-out of Reliance's contract across Scotland.

She has been given until Friday to release the terms of the deal between the firm and the Scottish executive to information commissioner Kevin Dunion.

Meanwhile, the Scottish nationalists have renewed their demands for the minister to resign.

"How many more prisoners have to be released before the Reliance contract is scrapped and Cathy Jamieson takes responsibility?" asked justice spokeswoman Nicola Sturgeon.

"The public are being put at risk and the justice minister cannot continue to pass the buck.

"She signed the contract that put Reliance in charge and when things started to go wrong she refused to scrap it.

"We cannot stand by while more and more prisoners slip through the net. Reliance must be taken off the job immediately.

"And Cathy Jamieson who should have done the decent thing and resigned over this fiasco weeks ago must now go.

"Jack McConnell must take charge of this matter personally and bring order back to our courts system."