A two-storey building under construction collapsed in Mamboleo estate, Kisumu county, on Monday.
Three women, who sold food to workers at the site, are believed to be trapped in the rubble.
Six others were rushed to Jaramogi Oginga Odinga Teaching and Referral Hospital with injuries.
Evacuation efforts are ongoing.
Kisumu East subcounty police commander James Musyimi said the building caved in at 1 .30pm.
Investigations have begun.
The Star is yet to establish the number of workers who were at the site at the time of the incident and the owner of the property.
This comes barely a week after a five-storey residential building which was leaning in Kinoo was brought down in a controlled demolition.
The building was last Monday demolished following concerns by residents.
According to the residents, trouble started when the caretaker noticed cracks and alerted the owner.
The owner returned to the scene in the morning after the building collapsed, but left shortly after without speaking to anyone.
Tenants in nearby houses vacated.
One of the tenants, who sought anonymity, told the Star she was hopeless and in a dilemma after leaving her belongings in her house.
"We are all in panic as we don't know what will happen next. As much as we need to get our belongings from the house, it is risky as the building might fall anytime," she said.
Masons at the site said they had noticed structural problems and informed the owner but no action was taken.
They said they noticed a crack on one of the columns on Thursday, prompting them to stop construction.
Edited by CM