A cyber criminal hijacked computers to spy on people having sex through their webcams, the National Crime Agency (NCA) has said.
Stefan Rigo, 33, used malware called Blackshades to give him control over strangers' cameras and spent five to 12 hours a day watching what they were doing in front of their computers.
The NCA said he was addicted to monitoring his victims, some of whom he knew and some who were complete strangers.
Rigo was given a 40-week suspended prison sentence, placed on the Sex Offenders Register for seven years and ordered to do 200 hours of unpaid work by magistrates in Leeds after he admitted voyeurism at a previous hearing, the agency confirmed.
A spokesman said Rigo was arrested in November last year as part of an international operation targeting users of software designed to remotely take over, control and steal information from computers.
He said the defendant used his ex-girlfriend's bank details to pay for and download the Blackshades malware, which gives the user complete control over target computers anywhere in the world.
The software can turn victims' webcams on and off, access banking or other personal information, download new and potentially illegal content, and instruct the victim's computer to help commit acts of criminality such as denial-of-service attacks.
The NCA spokesman said investigators found a series of images on Rigo's computer that involved people engaged in sexual acts over Skype or in front of their computers.
He said the defendant admitted using functions of Blackshades that enabled him to control webcams and monitor their desktops, enabling him to obtain passwords and email content.
Rigo, from Leeds, admitted voyeurism offences in September and has also admitted offences under the Computer Misuse Act.
Angela McKenna, senior investigating officer for the NCA's National Cyber Crime Unit, said: "People using malicious tools like Blackshades can massively violate the privacy of their victims, and use compromised computers to facilitate further crime.
"Users of these tools are continuing to find that despite having no physical contact or interaction with their victims, they can still be identified, tracked down and brought to justice by the NCA and its partners."
The NCA urged computer users to avoid clicking on unknown links, or files sent from unidentified or suspicious sources. Further guidance can be found at www.cyberstreetwise.com and www.getsafeoline.org.
It also urged anyone who thinks they might have been a victim of online crime to report it to Action Fraud, at www.actionfraud.police.uk.