The prime suspect arrested over the discovery of mutilated female bodies in a Nairobi rubbish dump had confessed to killing 42 women, according to the Kenyan police.
He also said that a second suspect, who was caught with a handset from a victim, was also arrested.
Acting Inspector General of Police Douglas Kanja said the 33-year-old prime suspect had been arrested at about 3am local time (00:00 GMT) near a bar in a joint operation by the Directorate of Criminal Investigations and the National Police Service.
He said a total of nine bodies had now been recovered so far and that autopsies on the victims would be carried out on Monday.
A video posted on social media also showed police presenting several pieces of evidence reportedly linked to the suspected killer.
Since Friday, mutilated and dismembered bodies – trussed in plastic bags – have been pulled from the rubbish heap in the Mukuru slums in the south of the capital, horrifying the country.
Police had said on Sunday the nine that had been recovered were all women.
Tensions ran high at the crime scene over the weekend, as furious residents were dispersed by police firing tear gas.
The discoveries have also thrown another spotlight on Kenyan police and added more pressure on President William Ruto, who is struggling to contain a crisis over widespread antigovernment protests that saw dozens of demonstrators killed.
The protests were triggered after the government raised taxes despite people struggling with the cost of living crisis.