An American man who ran a site that traded images of child sexual abuse has been jailed for 20 years.
David Lynn Browning was the central controller of the Playpen site, which was hosted on the dark web.
Browning will also be subject to a life-time of supervision when he eventually leaves prison.
He is the second key Playpen operator to be jailed. In January another administrator received a similar sentence.
Browning was a senior member of the group that had operated Playpen, said the US Department of Justice (DoJ) in a statement.
He had been responsible for the day-to-day running of the site, moderating discussions and managing membership lists.
The DoJ said the members-only website had been run via The Onion Router (Tor) anonymising network.
Tor bounces data requests through lots of different nodes, encrypting at every step to conceal who and where users are.
A long-running FBI operation led to Playpen being shut down in 2015.
Prior to it being closed, the FBI ran the site for two weeks, gathering data on its users.
Playpen is believed to have had about 150,000 members who shared tens of thousands of postings about the sexual abuse of children.
The DoJ said the FBI action had led to the arrest of 51 people connected to the site and to the rescue of 55 children who were being abused.
Browning’s co-administrator Steven W Chase, from Florida, who was also arrested as a result of the FBI investigation, is expected to be sentenced soon.