A prisoner told a jury how he gave his cellmate a "quick beating" after discovering he was a convicted rapist, but denied that he intended to cause serious harm.

Mervyn Plummer, 20, admits hitting Martin Young with a piece of wood and punching and slapping him, but denies causing grievous bodily harm with intent.

His co-accused Darren Walker, 22, of Wykham Road, Reading, denied the same charge.

Oxford Crown Court heard that the two men, and Young, were sharing a cell at Bullingdon Prison, near Bicester, when the attack happened in October, last year.

Walker told the court that he had nothing to do with the violence and urged Young to report the matter and get himself moved to another cell.

Plummer, giving evidence, said that his co-accused had nothing to do with the violence, but Young said that he did join in. The victim, who was convicted of two rape charges, claims that both men punched and kicked him in the head and stomach, and that a sauce bottle was smashed over his head.

He claims he was also bound and gagged and whipped with electrical flex during the incident, which lasted hours and left him with broken ribs, weals on his back and cuts.

Plummer, of Hulme, Manchester, told the court yesterday that Young had said he was in prison for armed robbery but he later found out, from a prison officer, that he was a rapist.

Plummer said he lashed out when his cellmate admitted his true criminal record while "smirking".

Plummer said that he gave Young a "quick beating" and struck him with part of a wooden table.

He then put him in a chair and tied his wrists together with shoelaces. He later set him free.

Plummer denied claims that he smashed a sauce bottle on Young, tied his legs together, and lashed his back with an electrical flex.

The trial continues.