The NSPCC says that over two million images of child sex abuse had been circulated by 100 offenders who went on to be convicted in the last 20 months.
In a sample created by analysing media reports of court cases from across the UK, the charity found that nearly 50,000 and videos confiscated were in the most serious categories of abuse, with some showing children and babies being raped by adults.
The investigation revealed that one in four of the offenders held a "position of trust" allowing them direct contact with children.
These included teachers, school workers, clergymen, medical professionals, police officers and a social worker.
The children's charity said the 'alarming' haul was enough to cover the football pitch at Wembley Stadium twice over.
"The scale of graphic child sex abuse pictures and videos over the internet is very alarming," the Mirror quoted Diana Sutton, NSPCC head of public affairs and campaigns, as saying.
"The number of images seized in these cases is enough to cover the pitch at Wembley Stadium twice over - and this is just a sample. Many more people were convicted for possessing, making and distributing indecent images of children online during the same period," Sutton added.