Republican frontrunner Donald Trump is backing his aide, despite the campaign chief being charged with assaulting a reporter.

Trump stands by campaign manager charged with battery over alleged reporter grab https://t.co/H4Do7ELwqP pic.twitter.com/l2u9ELCBT3

— Fox News (@FoxNews) March 30, 2016

A war of words and conflicting reports have emerged over exactly what happened, as CCTV footage shows his aide grabbing the journalist out of the way.

John Kasich if he would fire Trump's campaign manager: "Of course I would" #GOPTownHall https://t.co/5IleC1wZS4 https://t.co/dh4eN0DLxA

— CNN (@CNN) March 30, 2016

Helen Vaughan outlines what happened.