President Muhammadu Buhari has welcomed the “safe release” of 23 train passengers held hostage by gunmen since March.
Officials said the victims, who were found in terrible conditions, were being checked by doctors at a military hospital.
The military announced that a committee it set up had secured the release of the hostages, but gave no details.
The secretary of the committee, Prof Umar Yusuf,explained that no ransom was paid and there was no use of military force.
He said the victims had not changed clothes since they were abducted over six months ago.