An Oxfordshire computer expert who filmed himself raping a child has been warned to expect a life sentence behind bars.

Footage of Steven Langford sexually abusing victims as young as 18 months was handed in anonymously to police, Oxford Crown Court heard.

Langford, 34, from Bicester, admitted indecently assaulting a boy aged between 18 months and three years old in 2001 when he appeared yesterday.

He had already admitted 15 charges relating to incidents between 2001 and 2004 at an earlier hearing in October.

During that time he preyed on seven children, the court heard. He also admitted that he had downloaded a mass of pornographic images of children to his computer.

The full catalogue of abuse amounted to one charge of rape, nine counts of indecent assault against a child under 13, one charge of indecency with a child, one charge of indecent assault with a male person, two charges of making indecent pictures of children and one of possession of 80,000 indecent pictures of children.

The abuse came to light after the Thames Valley Police child protection unit was sent a DVD containing footage of the abuse.

Repeatedly describing the case as "awful", Judge Julian Hall adjourned sentencing until January 10 for a report by an expert in psycho-sexual disorders.

Remanding Langford in custody, the judge added that he was considering the "possibility of a life sentence".

Jennifer Edwards, prosecuting, said police had been sent footage of the crimes by an unknown source. Langford's company had then "hacked" further material from his computer hard drive, Paul Reid, defending, said.

"Everything he did was recorded on video," he told the court.

"He (Langford) says he does not know who sent the material in (to the police)."

Among the offences Langford admitted was raping a girl between the ages of four and six. Of the 17 offences he admitted, three related to his downloading of child porno- graphy.

Two matters of rape, which he denied, were permitted by the judge to lie on file.

The judge ordered that Langford's exact address should not be published. He said that he would have to view the video, about one and a half hours long, before sentencing him.