The girls went missing after jihadists stormed their school in the town of Dapchi in the north-eastern Yobe state on 19 February.

President Muhammadu Buhari said it was a "national disaster" and apologised to the girls' families.

The attack has revived memories of the Chibok schoolgirl abduction in 2014.

Anger has been growing among the girls' parents amid reports that soldiers had been withdrawn from key checkpoints in Dapchi last month.

(BBC News)