Prisoners staged a rooftop protest at an under-fire South Staffordshire jail this afternoon.
Three inmates staged the demonstration at HMP Oakwood, in Featherstone, which was recently criticised in a damning report.
G4S, the company which runs the prison, said the Ministry of Justice had been alerted.
A woman who claimed to be the mother of one of the inmates there, said her son had telephoned her to say three prisoners were demonstrating on the roof.
She said: “We don’t know exactly what the protest is about but inmates there are not happy.
“All of the other prisoners were ordered back to their cells.”
This evening, G4S confirmed the protest had ended without incident.
The £150million prison – which is the biggest jail in the UK – opened in April 2012 and houses 1,600 inmates.
Gavin Williamson, MP for South Staffordshire, said the main priority had to be the safety of the people who worked there. The reason behind the demonstration is not known.
Mr Williamson said he didn’t agree with the protest – but questioned how prisoners were able to get onto the roof.
“I don’t put a particularly high value on prisoners complaining about their living conditions,” the Conservative MP said.
“They shouldn’t have done the crime if they didn’t want to do the time.
“It’s disgusting that prisoners are protesting – they should be brought down as soon as possible.
“It looks dreadful for Oakwood and doesn’t present well for them at all.
“I’ll be wanting a detailed explanation as to how and why this protest has happened.”
Earlier this week the prison was dubbed ‘Jokewood’ following a damning report.
It emerged that inmates had told inspectors during a surprise visit that it was easier to get their hands on drugs than soap, while a report found that one in seven inmates develop a drug problem while inside.
Some prisoners also told how they felt unsafe in the jail, while staff were reported to be ‘passive and compliant, almost to the point of collusion’.
The chief inspector of prisons Nick Hardwick said the results had been ‘very concerning’ and ordered the prison to improve.