A man who blackmailed girls as young as 12 with fake nude pictures has been jailed for three years.
Sean McCuaig targeted nine girls between 12 and 17 by using a string of fake names.
He threatened to post the images of their faces "photoshopped" onto nude bodies for their families to see if they did not send him indecent photos.
McCuaig, from Knightswood in Glasgow, pleaded guilty to 20 charges spanning from January 2016 to June 2017.
They included downloading and distributing explicit pornographic images depicting women being raped.
The 22-year-old also had a total of 2,653 indecent images of children and 65 moving images, some of which were in the most serious category.
At Glasgow Sheriff Court, Sheriff Johanna Johnston QC told him: "This case involved you targeting young vulnerable girls on the internet over a lengthy period and persisting in a pattern of criminal behaviour.
"You menaced and frightened these girls and used their images for your own sexual gratification."
McCuaig will be supervised for three years after his release, and has been placed on the sex offenders register indefinitely.
The police investigation began in March 2017 after a 12-year-old girl contacted the Child Exploitation and Online Protection Centre.
Police examined his computer equipment and found files containing images of nude bodies which could be edited together with a face from a young girl's Facebook profile.
Earlier Glasgow Sheriff Court was told McCuaig set up fake Facebook profiles, often pretending to be girls.
He would then message his young victims a picture of a nude female with their face superimposed and threatened to post the image on Facebook if they did not send him pictures of themselves.
The court heard one victim said she would "kill herself" if McCuaig shared the images he had created.
However, after McCuaig started a countdown until she relented and sent him pictures of her bare legs and selfies.
Police also found a document detailing his fantasies of abducting, raping and hurting one of the girls, which included thoughts of killing her.
McCuaig was questioned about his offences in October and "spoke freely", confirming he was the person who wrote the fantasies document.
The court heard it included lines like: "I never want to do this but I am very scared I might succumb to these thoughts."
Defence lawyer Craig Grimes said his client knew he was going to be jailed, adding: "It's accepted by Mr McCuaig his offences and accepted fear and alarm cause to individuals was real."
A victim's story
Clare had just started a new school and was getting lots of Facebook friend requests, which she was keen to accept.
"I just accepted anything," she said.
This included a profile from someone claiming to be Phillip Greenhill, but which was actually Sean McCuaig, who she did not know.
Shortly afterwards, the 16-year-old got a Facebook message from Greenhill in the early hours of the morning.
It contained a picture taken from her Facebook profile, photoshopped on to a nude body.
McCuaig threatened to post the image for everyone to see if she did not send him a picture of her legs.
'Scared and shaking'
Clare, not her real name, said: "When I opened it I was shocked. I didn't know what to do.
"I was scared and shaking and I could not calm down."
She said she knew the picture was false but was worried that other people wouldn't realise that if it was posted to Facebook.
Clare said the man was confident he would get what he wanted and she got the impression he had done it before.
However, she knew she could not give in to his blackmail and went to her mother for help.
Her mum messaged McGuaig back, saying she was going to the police. He deleted his account.
Clare says she changed her Facebook name and privacy settings after the incident and it affected her confidence for a long time.
She did not go to the police and it was some time later before investigators contacted her.
The police investigation into Sean McCuaig's laptop had identified Clare as a victim.
She says: "This guy had been doing it for quite a while.
"I had thought he would just stop because he had deleted his account but he hadn't."
Clare says she feels guilty because she did not go to the police about it and McCuaig went on to have other victims.
"I was shocked and scared for the girls who were so much younger than me," she said.
"You don't know what they would do. They wouldn't know what to do except to comply."
Clare says she is pleased that McCuaig has been jailed and is facing the consequences of his actions.
She says: "It disgusts me. Nobody should do that to vulnerable young girls, or to anyone really."