The number of officers at a local prison has dropped by more than 100 in three years, making it a “dangerous” place, according to bosses of a reform charity.

It follows the publication of figures which showed the number of prison officers in the North West has fallen by 32 per cent.

Forest Bank Prison in Agecroft Road, Swinton — where many Bolton offenders are housed — had 204 prison officers in September, 2013 compared to 310 in September, 2010.

The Howard League for Penal Form (HLPR), which obtained the figures from the Ministry of Justice (MoJ), said the drop coincided with a rise in the number of prisoners and “an alarming rise” in self-inflicted deaths in custody.

But an MoJ spokesman disputed the figures, claiming the criticism is politically motivated.

HLPR chief executive Frances Crook said: “The prison system is at breaking point.

"Everyone should be concerned at the crisis in prisons as when people come out of jail they are more likely to inflict more crime on us.

“Ministers have used different figures to try to minimise the impact of prison closures, but the statistics show the true picture.

“Prisons are not just failing, they are dangerous.

“Violence and drug use is out of control and we will all suffer the consequences.

“This is the most irresponsible government penal policy in a generation.”

Mrs Crook added that one problem was that 18 prisons have closed and 6,500 prison places lost since mid-2010, while the number of convicts keeps on rising.

So far this year 43 people have taken their own lives in UK prisons, compared with 33 at the same point last year.

In 2013, the suicide rate was the highest in six years and the number of serious assaults was 25 per cent higher than 2012.

The MoJ spokesman said: “These are flawed and inaccurate figures from a left-wing pressure group, which can’t see past its dislike of this government.

“These figures present a misleading picture estate.

“Our approach to staffing levels has been agreed with the unions to ensure we run safe, efficient and decent prisons with prison officers back in frontline roles where they are most needed.

“Where there are local staffing issues, we are taking action to resolve this, including a widespread recruitment campaign and the creation of a reserve force of officers who can be used nationally when required.”