Chibok abductions in Nigeria: 'More than 230 seized'

At least 190 Nigerian schoolgirls remain missing after being abducted last week, their head teacher has told the BBC.

Asabe Kwambura said the parents of 230 girls had reported them missing, but 40 had managed to escape.

Earlier, a local state governor said that about 77 of the teenagers - from the school in the town of Chibok - had not been accounted for.

Aliyu Tanko reports.