POLICE investigating an attack on an al Quaida terrorist in a prison have questioned an inmate.

Dhiren Barot, the leader of a British-based al Quaida cell that plotted to murder thousands of people with dirty bombs, is scarred for life after an incident in Frankland Prison, Durham, in July.

His lawyer, Muddassar Arani, said an inmate threw boiling water over her client's back, which led to a fight.

Ms Arani said that later, while Barot was nursing his wounds, another convict poured what is thought to be a steaming mixture of sugar and water over his head.

Police last night confirmed that Barot has been interviewed and has made an official complaint, leading to a 22-year-old inmate being questioned last week.

No charge has been made against him, and police will hold talks with the Crown Prosecution Service to decide what to do next.

Barot, 35, from London, was once described by security sources as the second-most dangerous man in Britain, after Jordanian preacher Abu Qatada.

The Indian-born convert to Islam plotted to drive limousines packed with explosives into the New York Stock Exchange, flood the London Underground and considered using radioactive dirty bombs.

He was jailed for life in November last year and was moved, amid concerns for his safety, from Belmarsh Prison, in London, to Frankland shortly before the incident took place, on Monday, July 16.

Barot spent five days in the Royal Victoria Infirmary, in Newcastle, receiving treatment for burns, surrounded by armed police.

An air support unit was also deployed to the hospital.

Durham City MP Dr Roberta Blackman-Woods has called for Barot to be deported.

Frankland is a high-security prison, holding 730 criminals serving sentences of at least four-and-a-half years.

It also houses Omar Khyam, the ringleader of an al Quaida cell that plotted to blow up the Bluewater shopping centre, in Kent.