A police child protection officer has admitted downloading thousands of images of child pornography.

Iain Duncan pleaded guilty at the High Court in Glasgow to possessing 3,319 indecent images of children and 20 moving images.

The 28-year-old, of Bishopbriggs, near Glasgow, also admitted sending and receiving 326 indecent images of youngsters.

The former constable with Strathclyde Police was also found with a six-minute video showing "graphic images" of babies being abused.

He was caught after a police operation in Surrey which uncovered an email address he had been using.

Duncan has since resigned from the police, where he had been working in the Family Protection Unit at the time of his arrest.

Suspicions about the married father were sparked following an operation to catch another man who had been downloading child pornography.

That man was arrested in February 2007, and an email address he had been sending indecent images to was traced to Duncan.

Advocate-depute John Scullion told the court: "A police operation took place in Surrey, England, resulting in a male being charged with possession and distribution of indecent images of children.

"Subsequent investigation revealed email addresses of persons with whom this male had been exchanging indecent images."

On January 12 this year, Strathclyde Police called at the home of their fellow officer, where the door was answered by Duncan's wife.

He returned later and police questioned him about two computers he owned. After initially claiming the only indecent image on either computer was an 18-year-old female, he admitted at a police interview to having images of 13- and 14-year-olds.

After first examining the laptop, investigators then looked at the second computer and found images of children as young as ten.

Duncan, who was remanded in custody ahead of sentencing next month, also admitted sending and receiving images of an indecent nature to between ten and 20 people.

At the end of the interview, he said: "I know what I have done is wrong. I am sorry and ashamed."

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