Nigerian authorities said 281 inmates escaped after devastating floods brought down a prison’s walls in the country's northeast.

A major dam collapsed on Sept. 10, unleashing severe flooding that left 30 people dead and over a million displaced, and prompted evacuations across the state of Borno.

Officers attempted to evacuate the city of Maiduguri's main prison last week when they found out that the prisoners had escaped, Umar Abubakar, spokesperson for the Nigeria Correctional Services said in a statement Sunday night.

“The floods brought down the walls of the correctional facilities including the Medium Security Custodial Centre, as well as the staff quarters in the city,” Abubakar said.

Security personnel were able to recapture seven of the inmates and an operation is still ongoing to locate the rest, he said.

The collapse caused some of the state’s worst flooding since the same dam collapsed 30 years ago. The state government said the dam was at capacity due to unusually high rains.

Two years ago, heavy flooding in Nigeria killed more than 600 people across the country.

West Africa has experienced some of the heaviest flooding in decades this year, affecting over 2.3 million people, a threefold increase from 2023, according to the U.N.