The Kenya Red Cross said a multi agency response team was on site managing the operation. Local media reported that the building was around 16 storeys high.
Authorities have not yet commented on the cause of the collapse or confirmed the number of victims. Officials said the death toll was not expected to be high, though the rescue effort was still ongoing.
Building collapses are a recurring problem in Nairobi, where demand for housing remains strong. In the past, developers have been accused of ignoring safety rules and building codes. After a series of deadly collapses in 2015, an official audit found that more than half of the capital’s buildings were unfit for habitation.