A block of flats in the Sango Police Barracks in Ibadan, Oyo State capital, on Saturday evening, collapsed.
However, the number of trapped persons or casualties, if any, remained unknown.
The collapsed structure is in front of a residential three-storey building in the area.
A source with the National Emergency Management Agency (NEMA) who confirmed the incident.
The source, who said the agency got the alert around 8pm, also confirmed that Federal Fire Service have been mobilised to the scene of the incident.
The source confirmed that people were trapped and feared dead but could not authoritatively give any figure on casualty.
But the Director of Operations, Oyo State Fire Service, Ismail Adeleke said he has not been informed about the development.
All attempts to reach the officials of the Oyo State Police Command for comments on the incident were futile at the time of filing this report.
Meanwhile, residents in the area are intensifying efforts to evacuate the rubble.
