They say hundreds of inmates fought each other with home-made knives and clubs after rioting broke out at Barreto Campelo prison in the north-east of the country.

According to a police spokesman at the prison, the fight started when inmates from two prison wings invaded two others with the intent to kill 13 prisoners.

Police role questioned

BBC correspondent Jan Rocha "They were armed with home-made knives, stakes and clubs"

Although the police were called to the prison when the violence began, there are reports that they did not intervene to stop the fighting.

The riot lasted about an hour before guards were able to regain control. At least 70 of the prison's 200 cells were wrecked in the fighting.

At the end of the clash, 22 prisoners were dead and 13 injured. Five of the bodies had been burnt.

The authorities said the prisoners' attack was in revenge for the death of another prisoner last week.

However, the underlying issue is reported to be the control of the drug trade within the overcrowded prison.

The Barreto Campelo prison is located on an island near the city of Recife. It was built to hold 400 prisoners, but has nearly three times as many.