Supply teacher David Armstrong has been given a suspended jail sentence after admitting possessing over 4,500 indecent images of children.

Armstrong, 63, of Teasel Close, Devizes, was working at the Little Heath School at Tilehurst, near Reading, when the offences came to light, a judge at Reading Crown Court heard on Friday.

A teaching assistant noticed files on Armstrong’s laptop computer with file names such as “rape wife”, “nude model” and “gay alligator” and reported him.

Armstrong was subsequently arrested and found to have around 4,500 indecent images and videos on two laptops and an external hard drive – more than 300 of which were in the two most serious categories, some involving children as young as two.

Armstrong was given a 12-month jail sentence, suspended for two years, at Reading Crown Court on Friday for each of five charges of making indecent photographs or pseudo-photographs of a child between 2007 and 2010.

He had admitted the charges at an earlier hearing.

The court heard he realised he was attracted to children when he was in his 20s.

Judge Mary Jane Mowat said: “This was by any standards a substantial collection, with some 300 of the worst kind. You are 63 and this is your first conviction despite working as a teacher for 40 years.

“I don’t criticise you for being attracted to children. Many very good teachers are, but keep their urges under control.”

Armstrong was placed on the Sex Offenders’ Register for ten years, with a Sexual Prevention Order which bans him from owning a computer or device capable of connecting to the Internet, and ordered him to pay £500 costs and undergo treatment. He is automatically banned from working with children.

Robin Shellard, defending, said Armstrong, who is married and is the primary carer of his elderly mother, worked at many schools and colleges and has an impeccable record.

He said some of the pictures were not of real youngsters but of Japanese images depicting children and only 0.5 per cent were at the most serious level.