Don't forget to distinguish between what the Reg reports and what the Europol press release acutally says:
“Law enforcement agencies have to work together to combat the growing threat of cybercrimes against children, and we have to use the most advanced technology available. The complexity is huge and challenging - for example one of the Danish suspects had 29 terabytes of data that we confiscated. This is an incredible amount of data for our investigators to handle. To put it into perspective, that could hold about 9000 hours of high-quality video,” says Jens Henrik Hoejbjerg, Danish National Commissioner of Police.