Image caption L-R: Ndiku Mutua, Jane Muthoni Mara and Wambugu Wa Nyingi claimed they were tortured

Four elderly Kenyans have been told they can sue the Foreign Office for their alleged torture by British colonial authorities 50 years ago.

The High Court said the group could seek damages over their treatment during the 1950s and 60s.

Mr Justice McCombe said the claimants had an "arguable case" and it would be "dishonourable" to block the action.

Ministers say the UK government is not responsible for the actions of the colonial administration.

The decision means that the government will have to defend accusations of torture, murder, sexual assault and other alleged abuses at a full damages trial in 2012.

The four Kenyans, Ndiku Mutwiwa Mutua, Paulo Muoka Nzili, Wambugu Wa Nyingi and Jane Muthoni Mara, all in their 70s and 80s, say ministers in London approved systematic abuse in special camps. A fifth claimant has died since the action began.

Background The Mau Mau, a guerrilla group, began a violent campaign against white settlers in 1952

The uprising was put down by the British colonial government by 1960

The Kenya Human Rights Commission says 90,000 Kenyans were executed, tortured or maimed

It says 160,000 people were detained in appalling conditions

Kenya gained independence in 1963 Bloody uprising of the Mau Maus

The High Court heard that Mr Mutua and Mr Nzili had been castrated, Mr Nyingi was beaten unconscious in an incident in which 11 men were clubbed to death, and Mrs Mara had been subjected to appalling sexual abuse.

Mr Justice McCombe said in his judgement there was "ample evidence" to show there may have been "systematic torture of detainees during the Emergency".

"I emphasise that I have not found that there was systematic torture in the Kenyan camps nor that, if there was, the UK government is liable to detainees, such as the claimants, for what happened.

"I have simply decided that these five claimants have arguable cases in law and on the facts as presently known."

Lost documents

The trial is expected to include critical material from some 17,000 previously lost documents which were discovered earlier this year in the Foreign Office's archives.

The papers include detailed reports of atrocities which were sent to ministers in the 1950s and 1960s.

Analysis Professor David Anderson "This really is a landmark case. Firstly, for the Kenyans themselves, it is seen as a major statement of principle. "For many years in Kenya there has been a great resentment about Britain's failure to acknowledge what happened. Many in Kenya will be very relieved to have had this judgement. "It also has implications for Britain's imperial past. As a nation, we have been not very good at facing up to that history and I think this will help us do that and repair our reputation with our former colonies. "As well as the claimants named in this case, there are others in Kenya who suffered a similar fate. My best guess is that there may be as many as 1,400."

Some of the documents implicate British colonial officials in abuse at detention camps which were set up to smash the pre-independence uprising.

Professor David Anderson of Oxford University, who unearthed the documents, is working with other experts to log the potential evidence.

So far, the names of a further 600 apparent victims have been found in the papers, all of whom could theoretically sue if they are alive.

Martyn Day, solicitor for the Kenyans, said the ruling was a historic judgement.

"Over 50 years ago our clients suffered the most terrible torture at the hands of the British Colonial regime," he said.

"Our clients have been battling for years to obtain justice for what they endured. Our government has seemed hell-bent on preventing that happening.

"They want some sort of justice, an apology, some sort of money that would give them peace in their final years."

Government fights on

Foreign Office minister Henry Bellingham said: "It is right that those who feel they have a case are free to take it to the courts. We understand the pain and grievance felt by those, on all sides, who were involved in the divisive and bloody events of the emergency period in Kenya.

Image caption Mau Mau suspects were rounded up in camps

"Despite today's judgment, the government will continue to defend fully these proceedings, given the length of time elapsed and the complex legal and constitutional questions the case raises."

But Gitu Wa Kahengeri of the Mau Mau War Veterans' Association told the BBC's Focus on Africa that he welcomed the ruling.

The British were becoming "just people" and the veterans expected "reasonable compensation", he said.

"They tortured our people, raped our people, castrated our people," he said. "There is no evil they did not do. These atrocities are the cause of the case. We want them to pay for that," Mr Wa Kahengeri said.

Mr Justice McCombe has given the government until the autumn to prepare a defence and additional arguments that the case is too old to be heard.