LONDON — A primary school teacher who filmed himself sexually abusing girls during one-on-one reading sessions was jailed on Tuesday.

Nigel Leat was given an indeterminate sentence and told he would serve at least eight-and-a-half years for sexually abusing five girls over the course of five years at Hillside First School in Weston-super-Mare.

Leat, of Bloomfield Road, Bristol, pleaded guilty to 36 offences, including attempted rape of a child and sexual assault on children.

Judge Neil Ford at Bristol Crown Court told Leat his "treatment of the girls was clever, cunning, insidious and wicked".

"You were able to behave in this way because you were a teacher entrusted to look after children," he said.

The jury heard details of how the 51-year-old teacher got the girls to perform sex acts on him during private reading sessions.

Leat also filmed himself sexually abusing girls as young as six.

The videos were filmed in the school's staffroom and a resource room.

Police found more than 30,000 indecent photographs and 720 indecent movies in Leat's possession after he was arrested in December 2010.