A serial rapist carried out a catalogue of abuse against three women over a period of two decades.

Gerard Porteous was branded a "deeply dangerous man" after being convicted of the string of sex offences from 1994 to 2013.

The 56-year-old was jailed for 12 years at the High Court in Edinburgh on Friday, having been found guilty by a jury following a trial.

Judge Michael O'Grady QC told Porteous: "You have been convicted of an appalling catalogue of abuse against three women over a period of almost two decades."

He added: "You are a deeply dangerous individual and that requires me to afford what protection I can to the public."

The judge ordered Porteous should be kept under supervision for four years following his release from prison.

Mr O'Grady told him: "You have used and abused and degraded them in the most vile and disgusting fashion.

"I commend them for the courage they have mustered in speaking up against you."

Porteous began his sex offending in 1994 in Airdrie, North Lanarkshire, when he raped a 24-year-old woman and committed his final crime in December 2013 in Paisley, Renfrewshire, when he assaulted a woman with intent to rape her.

A jury unanimously found him guilty of four rapes, two assaults with intent to rape, an indecent assault, two assaults and two offences of causing fear and alarm to women.

Defence solicitor advocate Maurice Smyth said that standing Porteous' continuing denial of guilt he could not offer anything by way of mitigation to the court.

Porteous was earlier placed on the sex offenders register.