At least 40 people were feared killed when a dam collapsed in Gusau, northwest Nigeria.
More than 500 houses were washed away when the dam, the main source of water supply to the Zamfara state capital, gave way on Saturday.
State governor Ahmed Yarima confirmed the accident and called on the Nigerian government to provide aid to those rendered homeless.
He blamed state government officials for dereliction of duty and said action would be taken against those officials who did not take preventive measures.
Yarima said he was at a loss as to where to begin helping the displaced, most of whom were poor and did not have any alternative shelter.
He said he had ordered those confirmed dead to be taken to mortuaries in the state capital, while the government looked for ways of making survivors comfortable, until a long-term solution could be found.