A PRISON where an inmate was murdered by fellow prisoners was controlled by drug gangs, a court has heard.

Marcus Nelson, aged 30, and Aaron Gordon, aged 24, are accused of battering Patrick Butler to death at HMP Risley on November 13 2005.

At Chester Crown Court on Tuesday, a senior prison officer, who worked on C wing where the 41-year-old was killed, claimed drug gangs were rife.

Kevin Williams, the prison's third-in-command at the time of Butler's death, said: "Some of the major gang bosses in the drug supply would be located on C wing."

Earlier in the trial, it was alleged Nelson and Gordon, cousins by marriage, had attacked Butler in Nelson's cell, fracturing his skull.

Another prison officer, Stephen Taylor, said he was alerted to Butler's body, which had been dumped under a stairwell.

Mr Taylor said: "He was lying on his side, gasping for breath. There was blood round his head."

The court heard that Risley Prison traditionally took its inmates from Merseyside, Cheshire and Greater Manchester, but shortages in the prison system meant some offenders from the Midlands had to be held there too - Butler and the two defendants are originally from Wolverhampton.

Courtenay Griffiths, defending Gordon, said: "That has caused tension within prisons like Risley.

"It is a fact that gangs from Merseyside and Greater Manchester controlled Risley prison in terms of illegal activity.

"The majority of incidents of bullying stem from drugs or mobile phones - the contraband of choice in Risley."

The jury was told that a quarter of prisoners at Risley were drug users at the time Butler was killed.

Butler himself, a small-time but prolific criminal was a known heroin user.

Nelson and Gordon deny murder.

The trial continues.