A human rights panel has implicated the Kenyan police in the execution-style deaths of nearly 500 men, but the claims were dismissed out of hand by the security services.

The state-run Kenya National Commission on Human Rights (KNCHR) said the victims were executed with a single bullet between June and October.

More than 450 bodies were found in the capital's City Mortuary, 11 in the eastern town of Machakos, and another 11 in the Rift Valley town of Naivasha, the KNCHR said in a report on alleged executions and disappearances.

"Almost all the cadavers bear classic execution signs of a bullet behind the head exiting through the forehead," it said.

The findings "lead to the inescapable conclusion that the police could be complicit in the killing. The KNCHR is also extremely concerned that the emerging pattern points to possible complicity of state security agents in the disappearance of persons," it added.

KNCHR chief Maina Kiai called on police to explain how hundreds of bodies ended up in the mortuaries recorded on police registers, yet the force had flatly rejected any involvement in the deaths.

"There is need for a sense of accountability in our security forces ... Killing about 500 people without due process is a crime against humanity," Kiai told a news conference.

"We want police to tell us how those 500 people ended up in the mortuary between June and October. The burden of proof lies with the police."

Maina said that during investigations his panel had encountered "at all layers of the police hierarchy ... stonewalling, disinterest and outright denial of any knowledge on the killing and dumping of the bodies"

Police angrily dismissed the execution accusations as fodder for "horror movies".

"That is a very irresponsible statement. I do not know where they got the figures," national police spokesman Eric Kiraithe told independent NTV television.

"This is a very weird piece of imagination that would have passed as horror movie. I would like Maina Kiai to produce a post-mortem report from an authentic doctor declaring the cause of death," Kiraithe said.

The police declared months ago a war on the politically linked Mungiki religious gang, which was banned in 2002 after deadly slum warfare that killed dozens of people.

Once a religious group of dreadlocked youths who embraced traditional rituals, authorities say the Mungiki sect has morphed into a ruthless gang blamed for criminal activities including extortion and murder.

Since March, the gang has been accused of murdering at least 43 people - beheading several of their victims - mainly in Nairobi slums and central Kenya.

The wave of killings peaked in June, raising fears of widespread instability in Kenya ahead of general elections due in December, but a police crackdown that killed dozens of Mungiki suspects has since curbed the violence.

At the height of the crackdown, the London-based Amnesty International called for an immediate probe, saying police could be guilty of many human rights violations.

The claims come less than two months before the country holds a general elections with President Mwai Kibaki seeking a second and final term in office.

AFP