THOUSANDS of older prisoners are sharing jail cells during the coronavirus lockdown.

Chief inspector of prisons Peter Clarke told the Commons Justice Committee about 67 per cent of older prisoners, those aged 50 and over, are held in cells on their own, which is more than in any other age group, according to data he had seen.

He said: "That does mean there's about a third who are not held in single-cell accommodation, that of course with the current figures is somewhere just over 4,000."

Cases of coronavirus have been confirmed in more than half of jails in England and Wales and at least 13 inmates have died after testing positive for Covid-19.

Self-isolating or symptomatic prisoners and those who have tested positive are put in a cell on their own, but those who have not displayed symptoms may still be sharing cells with other inmates.

The Prisoners' Advice Service (PAS) has threatened legal action unless vulnerable and elderly prisoners were immediately released.

The Ministry of Justice (MoJ) plans to build 2,000 single-occupancy temporary prison cells in the grounds of seven jails in a bid to prevent the spread of coronavirus.

These would be used by low-risk category C and D offenders.

But Jo Farrar, chief executive of the Prisons and Probation Service, previously told the committee between 10,000 and 15,000 prisoners would need to be released so remaining inmates could have a cell each.

As of Friday, the number of criminals behind bars in England and Wales had dropped by more than 1,000 in a fortnight to around 81,000.

Although regular prison inspections have been suspended, some visits to scrutinise conditions are still taking place.

A total of 287 prisoners have tested positive for coronavirus in 65 prisons as of Monday 5pm, according to the MoJ.

Some 217 prison staff have also contracted the virus in 54 jails as well as eight prisoner escort and custody services staff.

At least 700 staff have been tested and more than 6,000 are self-isolating.

The MoJ pledged to release up to 4,000 low-risk prisoners on temporary licence in a bid to ease overcrowding, as well as pregnant inmates and mothers behind bars with babies, subject to passing risk assessments.

But the programme had to be put on hold after six inmates were released by mistake due to an "administrative error" and had to be sent back to prison.

Some 17 pregnant inmates and mothers with babies out of about 70 have been temporarily freed.

Lawyers acting for the Howard League for Penal Reform and Prison Reform Trust have launched legal action against the Justice Secretary, claiming measures so far taken to address coronavirus behind bars are "unlawful" because they will have a "manifestly insufficient impact".

Emergency coronavirus legislation states pregnant women, people aged over 70 or anyone younger with underlying health conditions are vulnerable and most at risk should they contract the virus.