A section of a storey building has collapsed in the Iyanaoloke area of Abeokuta, the Ogun State capital.
One worker is reportedly trapped beneath the rubble, while another escaped without injury.
The incident occurred at about 1:30 p.m. on Thursday.
Officials of the Ogun State Fire Service, alongside residents, are currently working to rescue the trapped victim from the debris.
The collapse has drawn a crowd of residents and passers-by to the scene.