Several female bodies were found in a Nairobi slum, Kenyan police said on Sunday.

Officers pledged a "transparent" and swift investigation into the killings, saying there were considering several options including serial killers, cults and rogue medical practitioners.

What do we know about investigations into the bodies?

Mutilated and dismembered bodies were founded in plastic bags at a garbage dump in the Mukuru slums of southern Nairobi.

Six bodies were found on Friday and additional body parts were found on Saturday, acting national police chief Douglas Kanja said at a press conference. Eight bodies were found in total.

Preliminary investigations revealed that all the bodies were female.

Criminal investigation chief Amin Mohammed, who spoke at the same press conference alongside Kanja, said that the ages of the victims ranged between about 18 and 30.

"They were severely dismembered in different states of decomposition and left in sacks," Kanja said.

He said that investigations were ongoing.

Kanja called for public cooperation "so that we bring the perpetrators of these heinous acts to book."

He said the police were committed to conducting "transparent, thorough and swift investigations" into the bodies.

Nairobi Governor Johnson Sakaja appealed for calm from residents of the area near the dumpsite. Kenyan daily newspaper The Star reported "altercations" with government officials.

Sakaja said the incident "hampered rescue efforts after police lobbed tear gas into the crowd."

Police search for culprits of killings

Last year, a mass grave was found on in a forest near Kenya's coast that contained the bodies of hundreds of members of a starvation cult. On Monday, cult leader Paul Nthenge Mackenzie and 94 co-defendants went on trial over the deaths.

Kenya's police watchdog, the Independent Police Oversight Authority (IPOA) said it was investigating whether there had been any police involvement in the dumped bodies found in Mukuru.

Kenya's police has been facing increasing scrutiny after dozens of people were killed in widespread anti-government demonstrations. Acting national police chief Douglas Kanja only took up the job on Friday, a week after the resignation of national police chief Japhet Koome over the protest deaths.

This article was written in part with material from Agence France-Presse (AFP).