At least 10 people were killed in separate places following heavy rains that were experienced in Nairobi on Sunday night and Monday morning.
The toll is expected to rise as more families have reported their friends and kin are missing following the flooding that was reported.
Among those missing is police constable David Chesire of Kamkunji police station who was swept by water as he saved a trapped family in the area.
His AK47 rifle with 30 bullets is also missing, police said. Efforts to trace the body on Monday did not bear fruits, police said.
Nairobi regional police commander Adamson Bungei said emergency teams collected 10 bodies from various places in the city on Monday alone.
He added they had not located Chesire but efforts to search for him are on.
“Some of the collected bodies do not have identification documents while others were naked. Raging water can strip one naked,” he said.
The bodies were collected from various places in the city.
The police boss said they had mobilized several emergency service providers to respond to various places and help in attending to those affected.
Kenya Red Cross said approximately 1,200 households had been identified as affected in various informal settlements with Mukuru Kwa Njenga and Mukuru Kwa Reuben being among the worst hit.
Some 52 households in Kayole were evacuated to safety after their homes were submerged by floodwaters.
They are currently being hosted at Kayole-Soweto Social Hall. Property was destroyed in the rains.
Nairobi Governor Johnson Sakaja visited some of the most affected areas and directed the Nairobi Water Sewerage Company to mobilise its water bowsers to be deployed there and also provide residents with clean water.
He also ordered the public health officers and Community Health Providers to intensify on-the-ground support through the distribution of water treatment tablets and offering psychosocial support to those affected.
"I want to appeal to our fellow brothers and sisters living along riparian and flood-prone areas to heed the calls of our disaster management teams to move from these areas," he added.
The governor said the county government is monitoring the situation and taking necessary measures to avoid further loss of lives and property.
Sakaja reiterated that the county was working with the national government, the National Police Service and the Red Cross to offer emergency support to residents.
He told the Green Nairobi, an army of persons hired by the county government to clean the city and unclog Nairobi drainage systems.
Sakaja directed the deployment of 170 Green Army personnel to unclog affected drainage.
He also asked the Disaster Management Team to collaborate with the NPS, Red Cross and National Disaster Operations Center in the search and recovery efforts for missing persons.
“Poleni sana to the affected families and our condolences for those who’ve lost loved ones. We stand in solidarity with you. We have deployed teams and machinery 24/7 for response in hotspot areas as mapped out. Call 1508 to report all emergencies,” he said.
The metrological department has warned of more rains in the coming days.