(BBC News) Islamist militant group Boko Haram was paid more than $3m (£2m) before releasing a French family of seven, a Nigerian government report says.
The confidential report, seen by Reuters news agency, does not say who paid the money.
Both France and Cameroon deny paying a ransom while Nigeria has not commented on the issue.
The French family, including four children, were captured in Cameroon in February and freed last week.
The Nigerian report also says that Cameroon freed some Boko Haram detainees as part of the deal, according to Reuters.