It has emerged that Justice Secretary Kenneth Clarke was warned about a lack of staff at Ford Open Prison two weeks before the riot took place.

The Independent Monitoring Board raised concerns to Mr Clarke regarding low staff numbers and junior staff monitoring the facility at night.

In a report, the board said: "Our concerns regarding night staffing are reported regularly.

"Our main concerns are minimal staff on duty and junior staff, who are only trained to a low level, patrolling alone.

"Whilst there have only been minor incidents in the last year we do not consider that proper control is being exercised at night."

The report added: "We are sceptical of the response received in the past that it must be adequate because there has not been a serious incident yet."

It is understood the riot erupted after guards attempted to breathalyse inmates for contraband alcohol in the early hours of New Year's Day.

As violence broke out at the facility, which holds around 500 inmates, only two officers and four support staff were on duty.

The guards were forced to retreat as the violence escalated.

Before authorities regained control, riot police and specialist prison officers were brought into force.

Extensive damage was caused to six accommodation blocks, a gym, mail room and snooker and pool rooms.

Earlier this week Mr Clarke told the Commons that lessons must be learned about what happened at Ford.

(BMcN)