Media tycoon Rupert Murdoch threw twitter into a flap with a controversial comparison between US President Barack Obama and Republican presidential candidate Ben Carson.
Murdoch's tweeted: "Ben and Candy Carson terrific. What about a real black President who can properly address the racial divide? And much else."
His use of the words "real black President" was widely panned as questioning Obama's race and identity.
Murdoch, 84, is the owner of Fox News Channel and co-executive chairman of 21st Century Fox.
