A damning report containing evidence of a high-level policy to murder suspected criminals and troublemakers in Kenya threatens to undermine the reputation of the government of President Mwai Kibaki.

The report, by the Kenya National Commission on Human Rights, reveals that in the past 18 months about 500 young men have been killed or have disappeared in a police campaign carried out with the apparent connivance of political leaders.

The dead and missing were suspected of being members of the Mungiki, a feared criminal gang that had itself committed gruesome murders.

The Mungiki was outlawed in 2002 following a spate of slum violence. It is a quasi-religious group from the dominant Kikuyu tribe and had become one of Kenya’s largest crime and extortion rings.

In a speech on June 1 last year, Kibaki warned gang members they should expect no mercy. Two days later more than 300 Mungiki members were arrested and 20 killed.

John Michuki, the internal security minister, said: “We will pulverise and finish them off. Even those arrested over the recent killings, I cannot tell you where they are today. What you will certainly hear is that so and so’s burial is tomorrow.”

Since then the commission has compiled the names of at least 300 men who have been killed or have disappeared. It also said there were about 200 victims whose identities could not be established since they were booked into the mortuaries as unknown.

Initially the police shot most suspects but then, the commission said, they turned to strangulation, drowning, mutilation and bludgeoning in an attempt to make the public believe rival gangs were responsible for the killings.

Several witnesses told the commission that police death squads carried machetes, iron bars, ropes and other crude weapons in their cars. Its evidence is being studied by the United Nations committee against torture.

A typical victim’s story came from Kagunda wa Mbui, a 45-year-old mason. Arrested on his way to work, he was savagely beaten with iron bars and rifle butts. The police burnt his dread-locks, a mark of Mungiki membership, by pouring paraffin over his hair and setting light to it. Finally they dumped him in the street. His wife took him to hospital but he died at the gate.

The commission believes the police were involved in an extortion racket in which they arrested individuals and then demanded money from relatives to secure their release. “These acts were ordered, directed or coordinated by the top leadership of the Kenya police acting jointly with a common purpose,” it stated.

The commission was set up in 2002 by the Kenyan parliament as an independent institution to protect human rights. A thorn in authority’s side, it has not always commanded popular support for attacking police rough justice in a country plagued by violent crime.

At the start of the year Kenya was torn apart by violence that erupted after Kibaki’s hotly disputed reelection. This led to a dramatic shift in public sympathy away from the police, who were blamed for shooting at least 400 of the 1,133 killed.

Last week as the commission called for a parliamentary inquiry and reform of the police, sources revealed that several of its officials who had worked on the report had fled abroad, fearing that if they stayed any longer they would be killed.

Their fears were heightened by the murder in broad daylight at the end of October of one of the commission’s main informants, Bernard Ngirinya, a father of two.

Ngirinya had been the driver for a police death squad that had allegedly carried out many of the killings in and around Nairobi. “He was physically present at many of the murders and was able to provide us with an account of what his unit was doing,” said one source.

Fearing for his life, Ngirinya went underground in Nairobi. But he was lured out of his hiding place and shot three times as he collected money from a cash machine.

“Dead men tell no tales,” said the source. “The police say he was a victim of crime. But we have his testimony on tape and it is the only protection we have, if it is true, that the police were really responsible for silencing him.”

The commission has handed its report, The Cry of Blood, to Kibaki and other senior Kenyan government officials, as well as to the UN.

It does not look as if it will be taken seriously by either the government or the police. Instead of acknowledging the gravity of the issue, Major-General Hussein Ali, the police commissioner, responded by calling the commission a meaningless busybody and challenged it to provide any evidence to back up its “rather infantile accusations”.

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