More than 180 teachers, social workers and other council staff were sacked last year after being judged to be a risk to children.
In 2012/13 some 3,651 local authority workers were investigated over allegations they had either harmed or abused children or were unsuitable to work with them, figures show.
The statistics – obtained following Freedom of Information requests to councils in England and Wales – show that 695 of those local authority probes were then investigated by police.
A total of 181 staff were subsequently sacked, according to council replies. Experts said it was the first time the total number of dismissals for such offences had been compiled.