A political agent and former Labour councillor has been jailed for three years for collecting and sharing images of child abuse.

Stephen Carnell, who was the Labour MP Chris Bryant's agent during last year's general election campaign, was caught with more than 12,000 indecent images and 450 films on his five laptops.

A large number of the images were categorised as level four and five, which are the most serious types of child pornography.

Prosecutor David Pugh said how Carnell had distributed and shared the images with other paedophiles over the internet.

Carnell, 58, worked as a Labour councillor in Tonypandy in Rhondda. He was also chairman of the board of governors at a primary school and had been on the board at another school.

"Carnell accepted he began viewing child pornography for his sexual gratification eight years ago," Pugh said.

"He said he was sexually interested in both male and female images. Carnell denied being sexually attracted to children in real life."

When police visited his home, Carnell let them in, saying: "The child pornography is on my laptops. I've been stupid."

He admitted 35 counts of making indecent images, seven counts of possessing such images and four counts of distributing indecent photographs of children between May 2003 and March 2011. The children ranged from 12-month-old infants to boys and girls up to the age of 11.

Judge John Curran said: "This is not a victimless crime: small children are subjected to the most appalling abuse for these photos and videos to be made.

"Anyone who is twisted enough to take part in this activity is going to be severely dealt with, especially as there is an element of distribution.

"This has been one of the largest number of images and movies I've ever had to deal with."

Carnell was ordered to register as a sex offender for life and banned from ever working with children.