Over 400 families have been left homeless after their houses were demolished in Kibera, Nairobi, on Thursday.
One of the affected residents, Akinyi Onyango, said teargas was lobbed into their houses early in the morning.
"Police officers were here as early as before 6am. They started by lobbying teargas and before we could salvage our items the bulldozers were already demolishing our houses," said Ms Onyango.
Two churches and two private schools were also demolished.
The residents said they received notices last month from the Kenya Railways asking them to relocate, but they did not know where to move to.
They said Kenya Railways was to relocate them once a slum upgrading programme funded by the World Bank was complete but people who were not beneficiaries of the programme were moved to the houses.
"This forced us to continue living here and now I have been left without a home," said Ms Onyango.
On Thursday, police engaged in running battles with rowdy youth who wanted to stop the demolitions.
The police officers had to use teargas to disperse them.
The police also forced the youths to surrender their phones to stop them taking photos. Journalists were also stopped by police from capturing the events.