Nairobi - A bound and mutilated body found dumped in a river outside Nairobi was identified on Friday as that of a Kenyan lawyer who disappeared last week after challenging police in court.A corpse believed to be that of young lawyer Willie Kimani was found late on Thursday wrapped in a sack and floating in the Ol Donyo Sabuk River. His wrists were bound with rope and his eyes appeared to have been gouged out. The cause of death has not yet been declared.The president of the Law Society of Kenya (LSK) said it was "a dark day for the rule of law in Kenya"."Our worst fears are confirmed. Advocates and citizens are at risk of elimination by police death squads," said Isaac Okero.The body was identified by friend and fellow lawyer Duncan Kinuthia. "I was in school with Willie Kimani, he was my senior and having known him for long, I can say that he is the one," Kinuthia said after visiting the mortuary. Family members were expected to formally identify the body later on Friday.Kimani's body was found alongside another - similarly bound and wrapped - believed to be that of either his client Josephat Mwenda or taxi driver Joseph Muiruri. A third body was spotted in the river, but has not yet been retrieved.Tortured 'a lot'"The bodies are in a very bad state and it seems they were tortured a lot before they were killed," said Kinuthia.Kimani disappeared on June 23 along with Mwenda and Muiruri after attending a court hearing at Makovo Law Courts on the outskirts of the capital. The case accuses local police of harassing and intimidating Mwenda in a bid to have him withdraw a complaint against a senior officer with the local Administration Police unit who he says shot him without provocation during a traffic stop in April 2015.On Wednesday, Kenyan lawyers protested outside the Supreme Court and a group of 11 human rights organisations issued a statement accusing police of abducting the three men."There is strong evidence indicating that Willie and his colleagues were unlawfully detained at the Syokimau [Administration Police] Camp for a period of time," the statement said.Kimani, a young human rights lawyer with the US legal aid group International Justice Mission (IJM), had a short but impressive track record defending political prisoners and victims of state abuse.Police chief Joseph Boinnet said on Friday that three officers had been arrested in connection with the killing, including an unnamed senior officer involved in the legal case."I have ordered the arrest of three police officers suspected to be linked to the disappearance of lawyer Kimani and his associates to assist in the investigations," Boinnet said.Kenya's police force has been accused in the past of running hit squads targeting those - including human rights activists and lawyers - investigating allegations of police rights abuses.