Rupert Murdoch has put his considerable influence behind black Republican candidate Ben Carson.

Calling for his 600,000 Twitter followers to watch Carson on TV show Kelly Rile on Monday, Murdoch then praised the candidate’s appearance.

The reaction was swift from Twitter users, many of them highlighting the tough job Murdoch’s public relations team must have defending his tweets.

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“Rupert your lawyer is on line two and screaming – what did you do??!?” wrote one user.

“Doesn’t News Corp have someone who holds Rupert’s smartphone for him so that this doesn’t happen?” wrote another.

Murdoch also suggested his followers read an article detailing the black community’s disappointment in Obama as president.

The conservative tycoon has made no secret of his dislike of Democrat Obama, the mogul himself a staunch Republican.

Mr Carson, a former doctor and author, responded to the mass shooting in Oregon last week by saying the public should be taught to rush at shooters with live guns.

“I would say, ‘Hey guys, everybody attack him. He may shoot me but he can’t get us all,'” he said on CBS’ This Morning.

Later on Facebook, the former doctor posted that although he had operated on victims of gun violence, “I never saw a body with bullet holes that was more devastating than taking the right to arm ourselves away.”