Officers from more than 40 police forces made more than 141 searches on warrants and arrested 76 people in raids as part of an operation targeting suspected internet paedophiles.
Those who were arrested included a Scout leader, a retired teacher and members of the Armed Services.
The officers who conducted searches were led by the Child Exploitation and Online Protection Centre (Ceop). Some 80 children were "safeguarded" following the raids. One in four were found at the properties searched by police.
Most of the warrants related to image offences, including the possession and distribution of indecent images of children, Ceop said. Among those arrested were a referee, a pathologist, Government employees, a firefighter, an outdoor activities instructor and a computer programmer.
Those arrested also included, known offenders who had breached the conditions of the Sex Offender's Register.
Ceop published a report warning that anyone caught downloading child abuse images online had the potentials of committing physical sex attacks on children. The report said that one analysis showed 55% of paedophiles who possess indecent images also commit sexual offences against children.
Kate Fisher, a principal analyst at Ceop, said the images being downloaded were more and more of extreme, sadistic and violent nature and featured increasingly younger children.
However, the severity and number of images held by offenders were in itself not enough to assess the risk they pose or the sentence they should receive, the report said. Ceop urged police forces to prioritize the investigation of anyone caught with child abuse images who had easy access to children.
Andy Baker, deputy chief executive at Ceop, said that it was clear that those who possess indecent images also pose a significant risk to children and understanding and managing that risk was not an easy job.
He added that when such nationally coordinated action by the police was taken up with operational support by the colleagues of the Serious Organized Crime Agency under the latest intelligence picture, it would make UK a more hostile place for those who seek to exploit the children.
Ceop called for the authorities to look beyond the quantity and severity of the images, adding that a full risk assessment should be considered before a judge hands down any sentence.