A preacher who stood as a Conservative candidate abused three young children he met through a Christian mission.

John Smart abused the youngsters, one from the age of three, over a 15-year period.

The 48-year-old met his victims at the Edinburgh City Mission where their parents believed he was a devout Christian and let him take the youngsters to play parks and swimming pools.

Smart, of Christian Crescent, Edinburgh, sexually abused the children between 1987 and 2002.

At the High Court in Glasgow on Wednesday, Lady Dorrian jailed Smart, who stood as a Tory candidate in 2003, for eight years and placed him on the sex offenders register.

Lady Dorrian told him: "The social enquiry report points out that these offences were planned, intrusive and involved a significant degree of planning. Your victims were vulnerable. You pose a sufficiently significant risk to children to merit a lengthy sentence."

Solicitor advocate John Keenan, defending, said that first offender Smart continued to protest his innocence.

Smart persuaded the parents of his victims to let him take the two boys and a girl on trips and also attacked them during overnight visits to his home. During his trial he denied the offences and claimed he could not have carried out the assaults because of a medical problem he was impotent.

The preacher claimed he did not know why the two boys and a girl he had abused, now aged 22, 27, and 29, had made the allegations against him. He told the trial he was "totally shocked" when he arrested by police.

Smart, who has led anti-homosexuality demonstrations and branded it "morally wrong", accused his victims of targeting him because he was so outspoken against their lifestyle choices. The jury found him guilty of five charges of abuse in Edinburgh, Leith, Peebles and Perth.