Sudan's death at the age of 45 leaves only two females of his subspecies alive in the world.
Campaign group says Nigerian army ignored repeated warnings of an attack on Dapchi hours before girls' kidnap, and more stories.
He is in custody for questioning over alleged campaign funding from late Libyan leader Gaddafi.
Broadcast time 09:50 GMT - 10:00 GMT
Broadcast time 10:06 GMT - 11:00 GMT
Broadcast time 11:06 GMT - 11:30 GMT
Broadcast time 13:06 GMT - 13:30 GMT