Robert Fury preyed on three girls and a boy between 1976 and 2002 at houses in Helensburgh and Dumbarton.

The 50 year-old was found guilty at the High Court in Glasgow of a string of charges including rape, using lewd and libidinous behaviour and assault.

Fury now faces a lengthy jail-term when he returns to the dock next month.

A jury heard how Fury raped a 17 year-old girl at a property in Helensburgh in 1991.

He had previously abused the same victim when she was younger and also assaulted her by punching her on the body.

The trial was told how Fury had already preyed on another young girl in the mid-late 70s starting when she was nine.

Fury went on to abuse a schoolgirl – in her early to mid teens at the time – at house in Dumbarton between 2001 and 2004.

His final victim was a young boy who Fury tormented at the same property between 1995 and 2002.

This included Fury forcing him to lie face down in a bath “for extended periods of time” and putting his head under water causing his breathing to be affected.

This victim – who was around nine when he was first set upon – also struck his head off a toilet after being assaulted.

He was later punched, slapped, hit with a belt and had a cigarette flicked at him.

Judge Lord Kinclaven deferred sentencing until May 13 at the High Court in Aberdeen.