The Ministry of Justice (MoJ) has instituted emergency measures to alleviate jail overcrowding as more rioters are being convicted for their involvement in the recent disturbances.

The Justice Secretary, Shabana Mahmood, has mandated that those awaiting court appearances in the north of England be detained in police cells until jail space becomes available.

Operation Early Dawn, the system, was turned on Monday morning. 

The Conservative government had already utilized it in May.

It will also mean some defendants will be released on bail for several days until a prison space is open.

The measure will be put in place in the North East and Yorkshire; Cumbria and Lancashire; and Manchester, Merseyside and Cheshire regions.

Ministers said efforts to “tackle violent thuggery on our streets” had “exacerbated longstanding capacity issues in our prisons”.

Lord Timpson, the prisons minister, said: “We inherited a justice system in crisis and exposed to shocks. As a result, we have been forced into making difficult but necessary decisions to keep it operating.”

He said that the emergency measures will help “manage the pressure felt in some parts of the country”. He added that anyone who poses a risk to the public “will not be bailed” and police’s ability to arrest criminals would not be impacted.

The MoJ has had to bring forward the use of 567 new prison cells that were earmarked to open at the end of this month to cope with the extra demand on prison space

As of Friday, more than 300 people have been remanded into custody for their role in the violent disorder that erupted after the Southport stabbings on July 29, with 460 arrests. Many more are expected to be arrested and charged as police leaders have vowed to track down offenders for “as long as it takes”.

Mark Fairhurst, the chair of the Prison Officers’ Association (POA) warned that it would have a knock-on effect throughout the criminal justice system.

On Sunday, he said: “This is all a result of the rioters. Last week we had the biggest influx of new receptions I’ve seen for quite some time. We had 397 new receptions. As of Friday we only had 340 spaces left in the adult closed male estate, which is feeling the most pressure.”

He said the move would put pressure on police forces: “You’re now clogging up police cells, so they haven’t got the power to arrest people and put them away in a police cell. It has a massive knock-on effect on the entire criminal justice system.”

Nev Kemp, of the National Police Chiefs’ Council, said: “We are working closely with criminal justice system partners to manage demand in the system and ensure that the public are safe.

“Policing will continue to arrest anyone that they need to in order to keep the public safe, including policing protests and events and ensuring that people are arrested as expected.”

It comes ahead of the launch of an early release scheme to tackle overcrowding. From September 10, thousands of prisoners will start being released 40 per cent of the way through their sentence rather than half way through their jail term.

It is expected to reduce the number of prisoners by some 5,500 to provide a breathing space for a major review of sentencing and for new jails to come on line.