Nairobi Governor Evans Kidero has reiterated all illegal buildings in the city will be demolished.
The county chief said many unapproved buildings in Nairobi are still occupied.
"Regularization of structures has been rolled out across the City, targeting critical areas that require urgent attention," Kidero said on October 18 on his official Facebook account.
"More than 50,000 buildings in the county have not been approved, yet they are occupied."
Early in the year over ten lives were lost when a building collapsed in Nairobi's East Lands.
Following the incident, Kidero promised to crack the whip and order for the demolition of all illegal buildings in the city.
The exercise, he said would begin in East Lands' estates since the area is the most affected.
He warned corrupt city engineers who connive with landlords to allow people live in unapproved buildings.