Victims of Kenya's independence war with Britain 50 years ago are to start proceedings to claim compensation from the British government
Veterans of the Mau Mau - who fought a guerrilla war with their colonial masters - are demanding an apology and an out-of-court financial settlement.
Tens of thousands of Mau Mau fighters were killed or imprisoned in camps.
"Many are in their 70s and 80s and would like to see reparations before they die," lawyer Martyn Day said.
Mr Day added: "We recognise the pain, suffering and torment that these freedom fighters have gone through - many of them are still suffering from the after effects today.
"We call on the British government to pay compensation to these people so that they can receive the justice they deserve."
Mr Day said the lawsuit would be filed next week, and the British government would have three months to decide whether to settle out of court.
If they do not get a satisfactory response, the Mau Mau say they will take their case to the High Court in London early in the new year.
The Mau Mau movement undoubtedly contributed to Kenya achieving independence in 1963, says the BBC's Adam Mynott in Nairobi.
It started in the European-owned farmlands in the Kenyan highlands in 1952.
Mau Mau fighters launched attacks on white settlers, spreading terror through the white farming community.
By 1960, the uprising had been decisively put down by the British colonial government.
The Kenya Human Rights Commission says 90,000 Kenyans were executed, tortured or maimed during the crackdown, and 160,000 were detained in appalling conditions.
An official report in 1961 determined that more than 11,000 Africans, most of them civilians, and 32 whites died during that period.
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