In May this year, around forty schoolchildren and staff from three schools were attacked and abducted by armed men in the southwestern state of Oyo. The country's army accuses the men of being Boko Haram jihadists.
The students and school staff were held hostage for 56 days before they were finally released by security authorities.
Several of the kidnappers were killed during the rescue operation and eight have been arrested, according to information from the authorities.
Kidnappings for ransom are a constant battle for authorities in Nigeria's troubled northern regions, but mass abductions in the southern parts of the country are unusual.
