The kidnapped sister of Nigeria’s oil minister, Diezani Alison-Madueke, who was abducted last week in the oil city of Port Harcourt, was freed in a joint operation by security forces, police said Wednesday.

“Osio Agama has been safely rescued during a joint operation by the police, military and SSS (State Security Service),” Rivers state police spokesman Ahmad Muhammad told AFP.

Muhammad did not say if ransom was paid for the release, the latest targeting relations of prominent Nigerians in recent months.