Nigerian police say they have located a camp where 19 national youth service recruits are being held by gunmen but cannot move in as they believe the place is mined with explosives.

Police Commissioner Audu Bosso said drones helped locate the camp where the prospective National Youth Service Corps (NYSC) members were taken after being abducted last week in the south-eastern Imo state.

The exact location of the camp has not been disclosed and police have not identified those responsible for the kidnapping.

Omotosho Adewale, whose child is among those abducted, told the BBC that the kidnappers had demanded a ransom of 50m naira ($37,680; £28,440), which he could not afford.

"There's no peace of mind. I've not eaten in three days," he said in between tears.

Adewale appealed to the government for help.

Those kidnapped had been travelling from Ibadan in the south-west to NYSC orientation camps in Abia and Akwa Ibom states on Thursday when gunmen attacked their buses near Umunoha in Imo state.

The NYSC is a compulsory one-year programme for most Nigerian university and polytechnic graduates. Participants, known as corps members, are posted to different parts of the country to work and take part in community service, as well as to foster a sense of national unity.