A mob in Western Kenya has killed a self-confessed serial killer who escaped from custody two days ago, police say.

Masten Wanjala was traced by villagers to a house in Bungoma town and beaten to death, they say.

Authorities had launched a massive manhunt for the fugitive who admitted to killing more than 10 young boys during a five-year period.

He also confessed to drugging them and in some cases drinking their blood.

He reportedly returned to the home of his parents - who have disowned him - and was subsequently strangled by neighbours who found out he was there, an eyewitness told Kenya's Standard newspaper.

He tried to stave off suspicious locals by moving to a nearby house, Bungoma's police commander told the paper.

It is thought his family identified the body.

"We are not sure how he managed to travel all the way from Nairobi to his rural home," Musyoki Mutungi said. "It is the curious villagers who first identified him and went ahead to kill him even before the police could be informed."

Wanjala posed as a football coach to lure his victims to secluded areas, after which he attacked them.

In some cases he took them as hostages for ransom.

Upon his arrest in July he took the police to burial sites of his victims where bodies have since been recovered.

Three police officers who were on duty when he escaped on Wednesday have been charged with aiding the escape of a suspect and negligence.

Police say they noticed he had disappeared during the morning roll call.

There are also growing calls for the resignation of Kenya's police chief over the escape, which shocked the nation.