Mysterious "cop" Hessy Wa Kayole has revealed the faces of the notorious thugs who were gunned down by police on Monday at Donholm, Nairobi.

Hessy took to the popular Facebook group "Kayole Crime Free" where he posted pictures of some of the suspected thugs before and after they were gunned down by police.

"#KingKahora na mbogi, mabandits walibakisha mechanic California -Eastleigh na wakadhani wataishi kuvuna through crime. RIHBs! #Donholm ndio mbio za sakafuni zimeishia. #CrimeDoesNotPay!!!" Hessy wrote.

Police shot dead the four suspected gangsters after an apparent robbery attempt in the estate.

Two pistols were recovered in the botched robbery.

Buruburu OCPD Geoffrey Mayek said the four suspects were accosted while robbing pedestrians at about 5pm.

He said the guns included a Ceska pistol which was stolen from an AP sergeant killed on February 15, 2014.

Mayek said one of the slain suspects was a wanted criminal who was behind robberies in Eastlands and Eastleigh areas.

"He was wanted following the incident where a businessman was robbed Sh2 million," the police boss said.