An IT specialist used his work and personal computers to create a library of over 40,000 child and animal sex abuse images.

Gary Warner, 41, pleaded guilty to a total of 21 charges relating to making and possessing images of children and extreme pornography, when he appeared at North West Wiltshire Magistrates’ Court on Friday.

The case came to light when Warner, who lives in Kingswood, near Bristol, resigned from his position as an ICT manager at Sherston Publishing Group, near Malmesbury, in 2008, where he worked for five years. Stephen Copeland, who runs the Sherston-based firm, checked Warner’s returned computer and mobile phone.

Kate Prince, prosecuting, said: “He checked the mobile phone and saw messages which indicated the defendant might have accessed child sex abuse images.

“The laptop was found to have been wiped clean by a faulty restoration of the operating system.”

Mr Copeland contacted the police and they found over 12,000 indecent images in various locations on the hard drive. All of those found were classed as level one images, the least serious category.

In October 2010 officers from Wiltshire Police arrested Warner at his home and found a number of computers and hard drives.

Forensic examination showed a further 30,000 child sex abuse images on various hard drives, as well as on 62 CDs and 12 DVDs.

The pictures ranged from level one to level five, with almost 2,000 in the two most serious categories. There were also 20 extreme pornographic images involving animals. Mrs Prince said police were particularly concerned as there had been an element of organisation of the files and images, into a form of library.

Warner, who was previously employed as a senior systems architect at global software company Emailvision, is being represented by Stephen Clifford and spoke only to confirm his name and address. Warner was told he would have to sign the sex offenders’ register within three days.

Magistrate Michael Sutton adjourned the case until May 14. Warner was released on bail, on condition he has no unsupervised contact with anyone under the age of 16.