Thousands protest Trayvon Martin 'injustice'

Several thousand people have taken part in a rally in the American state of Florida to demand the arrest of a crime-watch volunteer who shot dead the unarmed teenager Trayvon Martin almost four weeks ago.

Earlier the police chief of the city of Sanford, where the killing took place, temporarily stepped down from office amid the furore over his handling of the case.

The BBC's Paul Adams reports from Sanford.