A man who tricked children across the world into sending him nude selfies then blackmailed them into sexually abusing young relatives on camera has had four years added to his jail sentence.
Paul Leighton, 32, from Malvern Crescent, Seaham, County Durham, watched by video link from prison as three judges at the Court of Appeal in London raised his 16-year prison term to 20 years.
The judges agreed with Solicitor General Robert Buckland that the original sentence imposed at Newcastle Crown Court in September was "unduly lenient".
Spray-painter Leighton, who created up to 40 fake Facebook profiles to befriend teenagers in the UK, Canada, the US and Australia, admitted more than 20 offences, including rape, blackmail, causing a child to engage in sexual activity, making indecent photographs of a child, and sexual assault.
One 14-year-old from Florida was tricked into believing he was talking to a girl, then blackmailed into repeatedly raping his one-year-old niece.
Leighton (pictured) threatened the teenager that he would post videos of the abuse online if he did not do more.
Increasing his sentence on Thursday, Lord Justice Holroyde said of the crimes: "They involve sexual offending of a most serious and disturbing kind which has caused grave harm to a number of victims."
The judge said: "The offences involved the cynical manipulation of adolescent victims by communications over the internet, coupled with the use of blackmail."
Lord Justice Holroyde said the fact that he used some victims "to commit serious crimes against other victims - in one case a baby" made the overall picture one of "very grave offending."
The trial judge was faced with an "unusual and difficult sentencing exercise", and he was "plainly entitled" to reach the conclusion that Leighton was a "dangerous offender".
The court was in "no doubt" that 16 years was unduly lenient. As well as increasing the custodial term, the judges added one year to his six-year extended licence.
Mr Buckland said in a statement: "This is a deeply disturbing and serious case.
"Leighton callously targeted vulnerable children and subjected them to a series of threats, frightening them into complying with his sexual demands.
"Such terrible offending deserves a tougher punishment and this increased sentence takes into account the seriousness of this offending."
Copyright (c) Press Association Ltd. 2017, All Rights Reserved. Picture (c) Northumbria Police / PA Wire.