A Canadian woman kidnapped over a week ago in northern Nigeria is still being held, officials say, hours after police said she had been released.
Julie Mulligan, 45, was seized from a car by gunmen in Kaduna on 16 April.
A police spokesman earlier told the BBC she was in the custody of the security services, but the police later said Mrs Mulligan had not been freed.
A spokesman added that one of the gang who kidnapped Mrs Mulligan had been arrested and was in custody.
It is the first time a foreign woman has been kidnapped and held for ransom in Nigeria outside the restive oil-producing Niger Delta region.
Mrs Mulligan, a financial services consultant from Alberta, was travelling from a meeting with a friend when gunmen stopped their car and seized her.
Health fears
The kidnappers had said Mrs Mulligan was sick.
She had spoken to journalists on the phone since her kidnap and said she was afraid of getting malaria.
Local media reported her kidnappers had demanded 20m naira ($135,823; £92,000) to release her.
Kidnappings for ransom are common in the southern Niger Delta region, where militants and street gangs target wealthy Nigerians and foreign oil workers.
But this is the first time a foreigner has been kidnapped in the north of the country.