A total of 422 prisoners tested positive for the disease across 74 facilities as of 5pm yesterday, up 11 since the day before. Meanwhile 23 Prisoner Escort and Custody Services staff have been confirmed as having the virus.

North of the border 154 inmates have been granted early releases by the Scottish prison Service as part of efforts to contain the spread of coronavirus. Justice Secretary Humza Yousaf described the figures as ‘positive progress’ and said it has ‘helped to make prisons safe environments’.

The first early releases took place on May 6, according to an SPS report. None of the prisoners involved showed symptoms of Covid-19, which would have delayed the process. A governor’s veto was used in 23 cases to prevent early release.

Barlinnie let out the most inmates, at 25, followed by HMP Edinburgh at 19 and Glenochil, Kilmarnock and Low Moss prisons all at 17. A total of 445 prisoners are considered eligible for the scheme, which is being dealt with in three phases up to June 1.

It follows new legislation introducing powers for the early release of a specific class of inmates in Scottish inmates. This includes short-term prisoners nearing the end of their time in custody.

The scheme is limited to those sentenced to 18 months or less and who on had 90 days or less left to serve as of April 30.

Releases under the regulations are subject to exclusions to ensure public protection, such as those who are imprisoned for life or with convictions for sexual offences, domestic abuse or terrorism offences.

Meanwhile, the latest SPS figures indicate a total of 24 prisoners were self-isolating across nine institutions on Tuesday with one confirmed coronavirus case. The deaths of six inmates have been linked to Covid-19.

Statistics suggest there were 811 members of staff absent across the SPS as of Friday, which is 18.3% of the workforce. A total of 532 – 12% of those off – were absent due to Covid-19.

This includes those who are symptomatic, self-isolating, shielding or caring for family members. A total of 40 of these staff, 0.9% of the total workforce, are reported to be showing symptoms.

On April the Ministry of Justice announced plans to let out as many as 4,000 low-risk prisoners within two months of their release date. Selected offenders are released with electronic tags and can be recalled at the first sign of trouble.

The Government department bought 2,000 tags to monitor these inmates, but as of May 12 only 57 had been freed.

The ministry said its end of custody temporary release (ECTR) scheme was still going ahead and that alternative uses were being found for the surplus tags, the cost of which was not revealed.