Rescuers including Kenyan Red Cross search and rescue team is leading efforts to find people feared trapped and possibly killed.
The Red Cross said they managed to pull three children and an adult from the remains of the six-story building, adding that 150 building units and adjacent homes were affected.
Nairobi's Police Chief, Japheth Koome who confirmed the death toll said hours-long traffic jams caused by flooded roads delayed.
AP reports that man who said he lived in the house adjacent to the one that collapsed , said the building was constructed "shoddily" The building had been constructed in less than five months and the 126 single rooms were quickly occupied at a rent of $35 a month.
Area legislator Stephen Kariuki said this was the second building to collapse in a year. He blamed the county government of failing to follow through with demolitions of buildings that were identified as unfit for human occupation.
Source: Daily Nation/AP