Andrew Mitchell resigns over Downing St police row

The government chief whip Andrew Mitchell has resigned after weeks of criticism and speculation about his row with police officers in Downing Street.

The officers alleged that Mr Mitchell had abused them and called them "plebs" after they refused to let him cycle out through the main gates of Downing Street last month.

Mr Mitchell always denied using that term, but quit saying it was not fair to put his colleagues and family through such damaging publicity any longer.

Nick Robinson reports.