A six-story residential building collapsed on Friday night in Huruma, in the east of Nairobi in heavy rain, killing at least 12 people.
About 100 have been rescued out and 86 were receiving treatment at many hospitals in Nairobi.
Four rescue teams of Kenyan police, army, red-cross and local volunteers are searching for people who may by trapped at the disaster site on Sunday.
Narrow streets made it hard for excavators and large hoists to approach the collapsed building. Rescuers have to search for the survivors while digging broken walls with hands and tools.
The collapsed building sandwiched between two other residential buildings has been completely deformed with only the top three floors seen above the ground. Furniture and articles of daily use inside are exposed.
"When you have a view from here, you see that the building came down. So majority of the people, majority of the survivors are from that bungalow," said a local resident.
The building has 198 rooms and dozens are believed trapped in it. A woman was crying for help as her daughter and son-in-law were trapped in the building.
A Chinese-funded company sent two excavators and dozens of workers to help with the rescue. They were clearing the roads to facilitate the access to the disaster site.
Kenyan President Uhuru Keyatta came to the disaster site and said the building's owners should be arrested as the building was illegally built on a wetland.
Local residents have been asked to leave their homes for a safe shelter but some were unwilling to leave.
"Actually people should not be thrown away from here. I think we should look for means to, this building, they should build it up to the standards. We need like this building, they are not supposed to be here at first, because buildings are not supposed to be that immediate from the river. Now because of this corruption in this country, you see what is done to our colleagues and friends," said a local resident.