A RIOT squad was alerted to Portland Prison as a major disturbance broke out leaving one staff member injured.

Firefighters and paramedics were also called to HMP/YOI Portland as the prison service attempted to control the disturbance.

Following incidents on Wednesday, which led to firefighters being called on three separate occasions, there was further trouble yesterday when it was claimed some inmates had tried to flood their cells.

The drama continued well into the evening, with the Ministry of Justice claiming it was resolved only at 10pm on Thursday, having started at 9am.

A Prison Service spokesperson said: "Prison staff safely resolved an incident involving a number of offenders at HMP/YOI Portland.

"The offenders involved have been transferred to alternative establishments, and the prison is now returning to a normal regime."

They added that though there were no injuries to prisoners "one staff member suffered minor injuries but was not admitted to hospital."

The South Western Ambulance Service were made aware of the incident about 9pm but were not required to attend.

Four inmates triggered the incident on Wednesday by climbing on netting between landings at the jail.

Initially, three fires were reported in cells although it was claimed by a prison source that there were in fact many more.

The source claimed that there were as many as 12 fires, and he disputed claims from the Prison Service that no damage had been caused. He also claimed the prison was ‘locked down’.

The source said: “There were indeed four prisoners who managed to get onto the netting between the landings. However, there were at least 12 cell fires. The prison was locked down because of the multiple cell fires.

“Prisoners smashed up their cells, causing a large amount of damage.

“The fire brigade were there for most of the evening and national riot teams were called in.”

The source claimed the incident ‘wasn’t a one-off’ and said staff had expressed concerns about returning to work there after the disturbance.

The Prison Officers Association could not be reached for comment.

A spokesman from Dorset fire service said crews were called out three times to the prison on Wednesday – at 5.18pm, 7.05pm and finally at 7.30pm.

They added that a crew were called again this morning, but a fire had been extinguished before crews arrived.

A Prison Service spokesman said: “Four prisoners at HMP/YOI Portland climbed onto the netting between landings at about 4.20pm on Wednesday.

“Staff worked with the tactical response team to safely bring them down by 8.20pm. All four prisoners are now in segregation.”

He added: “Staff also responded quickly to extinguish three very small cell fires. No staff or prisoners were injured, there was no damage to cells, and there was no wider disruption to the establishment.”

Today, a further disturbance was reported at the prison, starting at 9am and continuing into the evening.

The Prison Service spokesman said: “An incident involving a number of offenders is currently taking place at HMP/YOI Portland.

“Specialist prison officers are working to resolve this as quickly and as safely as possible.”

Rob Preece, campaigns and communications manager at the Howard League for Penal Reform, said: “Disturbances such as this have become increasingly frequent in prisons across the country.

“Only last week we learned that incidents of concerted indiscipline have soared by 207 per cent in three years, as prisons struggle to contend with rising prisoner numbers, chronic overcrowding and deep staff cuts.

“We cannot go on cramming more and more people into jails without any thought for the safety of staff, prisoners and the public.”