They've just named the nursery worker being questioned over distribution of child porn images. She has not, as yet, been charged with an offence - she is still being questioned.
Similarly I remember when several prostitutes were murdered in ipswich, a man being questioned was named, and his address was published in the national media. He was later released without charge and someone else was later found guilty of the murders.
Now don't get me wrong, once someone is charged/convicted of a crime they should be named. But beforehand this is just wrong, surely? what happens if you name a suspect and they turn out to be innocent? mud still sticks.