Prisons could release some offenders to ease the pressure caused by coronavirus, a Cabinet minister has said.

Jails in England and Wales were put on immediate lockdown last night with all visits cancelled as it emerged thousands of staff were in self-isolation.

Jo Farrar, chief executive of the Prison and Probation Service, told the Commons Justice Committee that 13 inmates had tested positive for coronavirus with confirmed cases in nine prisons at present - although others were suspected to have been affected.

© Provided by Daily Mail Jails in England and Wales were put on immediate lockdown last night with all visits cancelled as it emerged thousands of staff were in self-isolation (pictured: HMP Pentonville) She said overall around 4,300 prison and probation staff were self-isolating at the moment. Some 3,500 were prison staff - representing about 10% of the workforce.

Around 50,000 protective masks have been delivered for staff to use and a ban on bringing hand sanitiser into the prison had been lifted.

Justice Secretary Robert Buckland did not rule out considering releasing prisoners when asked if this could help ease the pressure on prisons.

© Provided by Daily Mail Justice Secretary Robert Buckland did not rule out considering releasing prisoners when asked if this could help ease the pressure on prisons

Mr Buckland told the committee: 'I have to bring that as part of the equation.'

But he said that risk would 'have to be considered' as well as looking at options such as making use of release on temporary licence, bail accommodation and working out 'what to do' with some 9,000 prisoners currently on remand.

He explained that 'quite a proportion of the estate where there is crowding - that presents a real challenge' and many inmates were vulnerable or had underlying health conditions.'

There are hopes to roll out tests for Covid-19 to staff in self-isolation, MPs sitting on the committee were told.

The news comes after concerns were raised about conditions at HMP Holme House in County Durham.

Related: UK prison life revealed (Photos)

A source said there was a lack of protective equipment for staff as well as a shortage of soap and cleaning products.

Lockdown measures inside jails will include:

* A ban on social visits but efforts made to make more phones available to inmates

* Prisoners generally being locked up but allowed to access showers, phones and exercise - with social-distancing restrictions in place.

* Those who carry out kitchen, cleaning and laundry work will be allowed to continue.

* Gyms have been closed.

* Activities such as education suspended Prisoners are also not being brought to court for hearings, it is understood

Stay at home to stop coronavirus spreading - here is what you can and can't do. If you think you have the virus, don't go to the GP or hospital, stay indoors and get advice online. Only call NHS 111 if you cannot cope with your symptoms at home; your condition gets worse; or your symptoms do not get better after seven days. In parts of Wales where 111 isn't available, call NHS Direct on 0845 46 47. In Scotland, anyone with symptoms is advised to self-isolate for seven days. In Northern Ireland, call your GP.