Authorities in Nigeria are releasing hundreds of people accused of supporting an Islamic extremist group, citing a lack of evidence.

Salihu Othman Isah, a special adviser to Nigeria’s attorney general, said in a statement on Sunday that 475 suspects will be sent to rehabillitation instead of facing trial.

They are among the more than 1,000 suspected Boko Haram members whose trials began last Monday at a military barracks in the central Nigerian town of Kainji.

The suspects were accused of belonging to Boko Haram or for concealing information about the group.

Nigeria’s President Muhammadu Buhari recently said the era of Boko Haram terrorism “is gradually drawing to end”. However, the group continues to launch suicide bombing attacks in the country’s northeast and its leader remains at large.