Deep in the subterranean, windowless dungeon of a prison dating back to Victorian times, a young man contemplates his fate.

The air is filled with the stench from a blocked toilet while cockroaches scuttle across the floor.

Rats roam freely — so numerous that inmates lure them to their cells and then kill them to alleviate the crushing boredom.

Elsewhere, things are little better. Pigeons fly in through broken windows, further soiling rubbish-filled communal areas.

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A man holds a sign, reading 'Help. No Food' from the window of HMP Bedford in November 2016. Sheets are laundered only once a month and showers are a rare luxury — one amputee has washed only five times this year so far

Amid the filth, the inmates struggle to maintain their personal hygiene.

Sheets are laundered only once a month and showers are a rare luxury — one amputee has washed only five times this year so far.

All the while, the air hangs heavy with simmering tension.

Drug use is rampant — up to half of all inmates being users, with many having only turned to drugs since their incarceration. Levels of suicide and self-harm are shocking.

Prisoners at HMP Bedford went on the rampage inside the category B prison. Inmates were locked up for up to 23 hours a day in overcrowded cells in 2016

Gangs control the narcotics trade and outbreaks of violence between rival groups are commonplace.

Guards, more than three-quarters of whom have less than a year's experience, battle valiantly to keep a lid on things. But they are understaffed and the terrifying reality is that it is the prisoners who run the prison. And they know it.

Two weeks ago, five warders were taken to hospital — a woman with broken ribs, others with bite wounds — after a mini-riot broke out.

Earlier this year, a male colleague had his head stamped on in an incident, leaving him requiring brain surgery.

Welcome to Bedford Prison — a place where conditions are worse than when the jail was rebuilt more than 150 years ago.

Of course, many would argue that anyone serving time should not expect a cushy ride.

But the fact that conditions have deteriorated to such a degree in this prison is a national scandal. Indeed, it's not just Bedford.

On Sunday, six prison officers were injured, including one who suffered a suspected broken jaw, during a riot at HMP Long Lartin in Worcestershire.

Last month, a report by the Chief Inspector of Prisons, Peter Clarke, showed how staff had lost control of Birmingham jail.

Inmates were said to be openly taking drugs, carrying out assaults and behaving with 'near impunity'. The report said the prison, run by G4S, was in 'a state of crisis' and host to 'appalling violence and squalor'.

It described prisoners roaming unchecked while 'fearful' staff locked themselves in their offices or slept when they should have been on patrol.

Most worryingly, this is not a recent, temporary problem. In 2016, a riot broke at Bedford causing £1 million worth of damage.

The cause? Overcrowding and understaffing that meant inmates were locked up 23 hours a day.

Also, there were shortages of toilet paper and soap, while a lack of envelopes meant a four-week wait to send a letter.

And yet, conditions have deteriorated since then.

The decline has been charted in official reports, emergency interventions and the jail being put in 'special measures' in May.

Two prisoners inside HMP Bedford take a selfie with riot squad helmets in 2016. A Category B jail, it mainly serves the courts in Bedfordshire and Hertfordshire and receives remand and post-conviction prisoners, prior to their allocation to other jails

Members of the POA, the trade union for prison staff, protested outside HMP Bedford earlier this month after a damning report warned of a 'dangerous lack of control' at the jail

But when inspectors made an unannounced visit last month, they were so shocked that they took immediate action.

The Chief Inspector of Prisons initiated the Urgent Notification process, writing to the Justice Minister to warn of his findings.

The minister has 28 days to publish a response and a plan of action. Last month, Michael Spurr, the head of the Prison Service, was forced out.

'The clear view of the Inspectorate is that immediate and decisive intervention is needed at HMP Bedford to avert further decline and an even more dangerous lack of control than is currently the case,' wrote Mr Clarke, the chief inspector.

It is a view confirmed in interviews conducted by the Mail this week with relatives, prison insiders and officials.

All fear that the well-being and lives of prison guards and inmates are at risk.

What's more, Mr Clarke believes that what's happening in Bedford and other prisons has a profound effect on the wider society. 'Ultimately, the people who are suffering are not only the prisoners but the public,' he said.

'Because people are emerging from prison back into the community embittered, frustrated and, one in five from Bedford, with a drug habit which they didn't have when they went into prison.

'Therefore, because of all those things, they are much more likely to offend.'

Located in the middle of town, Bedford prison was enlarged in the mid 19th century.

Many of the elements of those Victorian works remain, including a number of three-storey wings radiating off a central hub.

A Category B jail, it mainly serves the courts in Bedfordshire and Hertfordshire and receives remand and post-conviction prisoners, prior to their allocation to other jails.

So, about 80 per cent of inmates stay for less than six months and the prison has an annual throughput of up to 3,000 men.

While its Certified Normal Accommodation — the ideal level aspired to by the Prison Service — is for 310 prisoners, its operational capacity is 487. In other words, it's seriously overcrowded. Also, it is short of staff — particularly experienced ones.

Professor Geoff Shepherd, vice-chairman of the Bedford Independent Monitoring Board, has visited the prison every week for the past three years. The board is a voluntary body which produces an annual report and liaises between prisoners and prison authorities.

When Professor Shepherd last visited, he learned of the 'mini riot' which broke out two weeks ago.

Two days earlier, prisoners in one wing had refused to return to their cells. Then, a fight broke out that resulted in five officers being injured and control being lost over much of the prison.

Reinforcements were summoned with so-called Tornado squads of riot officers equipped with helmets and shields.

I'm told that only the deployment of dog-handlers prevented the situation turning into another full-scale riot.

Since then, 30 prisoners identified as ringleaders have been moved from the prison.

The previous weekend, the Mail has learned, had seen another serious incident — a fight between inmates and visitors.

'The prison is in a very unstable state at the moment,' said Professor Shepherd. He said that officers had candidly told him recently that 'half the time they didn't know what to do'.

Prison officers needed riot protection equipment to quell the violent outburst in 2016

The 2016 riot, pictured above, caused extensive damage to the prison fixtures, fittings and doors. Attacks on staff have also risen dramatically in number — the rate in Bedford being the highest in the country, with 116 recorded attacks in the past six months

He added: 'It's a very complicated job running a prison — you only learn those things on the job or by having people to ask what is the best way to do things.'

The truth is that Government cuts have seen the number of frontline prison officers fall dramatically.

In the week before the 2016 riot at Bedford, only 55 out of a complement of 110 warders were on duty.

This meant prisoners were confined to their cells, sparking frustration and the subsequent violence.

After that riot, steps were taken to increase the number of officers. This worked — to a point.

However, Professor Shepherd says the new recruits were younger and less experienced — 'basically they were all straight out of training school'. Indeed, official figures show that earlier this month, 77 per cent of available officers had less than one year's experience.

Professor Shepherd says the shortage of officers means control over the prisoners is limited, to say the least.

This chimes with the view of a relative of an inmate who told the Mail that prisoners 'are like kids and they need to be taught to show some respect'.

As for concern the jail is out of control, one of the prison inspectors was pelted with food during their visit.

When he tried to investigate, staff were unwilling to intervene — which, prisoners said, was 'not unusual'.

Separately, when a prisoner found in possession of an illicit mobile phone began to protest, he incited other prisoners to join in.

'Staff struggled to deal with the incident, and appeared not to know what to do,' observed the inspector. 'What happened was not a controlled negotiation leading to a resolution, but a case of inexperienced staff capitulating to aggressive prisoners.'

The situation is made more volatile by the widespread availability of drugs.

One prisoner in five in Bedford jail says they've acquired a drug habit since arriving there.

The smell of cannabis pervades the blocks — despite smoking of any sort being banned.

The concerned father of one young inmate said: 'There are a lot of drug zombies.

'Some get letters sent in that have been soaked in Spice [a psychoactive substance] and they lick it off.' The issue is so bad that it is suggested that all mail will have to be photocopied — and the copies given to the prisoners, rather than the originals.

Then there is the problem of so-called 'throw-overs' — packages of drugs being thrown to inmates over the prison walls.

Surreally, it has been said that some people get themselves sent to the prison just so they can sell drugs inside.

Fights for control of the drug trade are commonplace — as is retribution directed at those who run up debts.

Problems recently include a prisoner housed in a cell that was meant to be out of use as it had no furniture, a broken window, a toilet that did not flush and builders' rubble on the floor from unfinished repairs. Given such conditions, it is hardly surprising that the mental well-being of prisoners has suffered [File photo]

Unsurprisingly, levels of violence at the prison are shocking.

Over the past 12 months, only Birmingham jail has a higher rate of assaults. Attacks on staff had also risen dramatically in number — the rate in Bedford being the highest in the country, with 116 recorded attacks in the past six months.

In March, an officer required life-saving surgery after his head was stamped on.

'I have seen horrendous assaults this year: detached eye sockets, broken jaws, broken limbs, young female officers being spat at and having excrement and urine thrown at them,' said Steve Gillan, general secretary of the prison officers' union.

'I've been in the prison system for 28 years but have never known it as bad.' He blames reduced prison officer numbers. Of particular concern is the segregation unit.

Professor Shepherd says: 'It's a dungeon — below the ground with no natural light.

'The cells are disgusting. There are cockroaches from the floor above infesting the whole place and the toilets are continually breaking down.'

He says he has heard 'rats chirping to each other' in the walls of the showers.

It was in the segregation unit where a 'disturbed' prisoner was seen luring rats to his cell and killing them.

Professor Shepherd says that in their annual report, to be published next month, the Bedford Independent Monitoring Board will call for the unit to be immediately shut down.

Other problems observed recently include a prisoner housed in a cell that was meant to be out of use as it had no furniture, a broken window, a toilet that did not flush and builders' rubble on the floor from unfinished repairs.

Given such conditions, it is hardly surprising that the mental well-being of prisoners has suffered.

In the past six months there have been 163 incidents of self-harm — and six suicides since the start of 2016.

The problem is exacerbated, says Professor Shepherd, because of the high number of prisoners on remand, waiting to go to court.

'They're known to have much higher rates of mental health problems because on remand you don't know what is going to happen to you,' he said.

In 2016, a prisoner who suffered from schizophrenia hanged himself at the prison while he was on remand for robbery.

An inquest jury criticised the jail authorities, saying failures and missed opportunities contributed to his death.

Speaking to the Mail this week, the dead man's mother, Christine Garside-Neville, 62, shared the note he had left which revealed his sense of desperation.

'Tell my family I cant cowp [sic] with prison life and that it brings,' he wrote.

The air is filled with the stench from a blocked toilet while cockroaches scuttle across the floor. Rats roam freely — so numerous that inmates lure them to their cells and then kill them to alleviate the crushing boredom [File photo]

'Cant wait until my court date. 22 weeks of a not guilty plea and you wonder y I killed myself. Wrongly imprisoned and can't hack the pace locked up when I should be walking the streets. RIP Mark . . .'

His mother added: 'He was vulnerable and easily led. He needed to be in a special psychiatric unit.

The prison was operating with a skeleton staff — there were not enough people around and those who were there were not properly trained.'

Asked about the problems at Bedford, a spokesman for the Ministry of Justice referred the Mail to a statement issued by Prisons Minister Rory Stewart.

It said: 'Bedford prison faces serious challenges.

'We placed it in special measures before the inspection was conducted and we are bringing in senior experienced managers.

'Our focus will be on reducing violence and drugs, along with supporting our prison officers to turn Bedford around.

'It is abundantly clear that further action is needed.'

Perhaps the last word should go to the prisoners.

In the clear-up following the riot in 2016, hand-written notes were found that inmates had stuck to the walls.

One simply stated: 'We need to be treated like human beings.'