Mystery surrounds the fate of more than 100 teenage girls who were abducted from a school in the remote north-east of
US President Barack Obama is to nominate John Brennan as the next director of the Central Intelligence Agency, the White House has said.
Mr Brennan, who has worked for the CIA for a quarter of a century, is currently the president's chief counter-terrorism adviser.
Mr Brennan, who was considered for the role in 2008, is to be formally nominated later on Monday.
His appointment must be confirmed by the Senate.