More than 270 prisoners are now missing, according to Nigerian authorities, who escaped from prison when a prison in the northeastern city of Maiduguri was damaged by heavy flooding.
So far, seven have been re-arrested.
The flooding was caused by the collapse of a dam after heavy rainfall.
Hundreds of thousands of people in Maiduguri, the capital of Borno state, have been forced from their homes by floodwaters and at least 30 people have died.
Borno State Governor Babagana Zulum described the extent of the damage as “humanly unimaginable”.
This is the first time that Nigerian authorities have admitted the number of people who have fled.
The Nigerian Correctional Service (NCoS) said on Sunday that after the walls of the medium security prison were damaged, inmates were transferred and some managed to escape during the “evacuation to a safe and secure facility”.
Governor Zulum had earlier told the BBC that members of the Islamist militant group Boko Haram were among those who escaped.
However, it is unclear how many of the fugitives have links to jihadist violence.
NCoS spokesperson Umar Abubakar has assured the public that his organisation is working with security agencies to recover the escaped persons.
The organization has published photos of the missing men and is calling on people to remain calm. According to the organization, the escape has no consequences for public safety.
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