Donald Trump tweets about 'sex tape' in beauty row

It was the American singer-songwriter Meghan Trainor who pondered the wisdom of reaching for one's cellphone in the early hours.

"3am, yo I'm texting you once again, Even though I'm hanging with my friends," she sang in her 2015 hit 3am.

Donald Trump also appears to have a problem steering clear of his phone when he ought to know better.

In his latest barrage of tweets, which began at 3am, the New York tycoon began condemning unspecified articles in the media that had appeared about him.

"Anytime you see a story about me or my campaign saying "sources said," DO NOT believe it. There are no sources, they are just made up lies!," he said.

The Republican candidate swiftly moved on to the subject of a former beauty pageant winner, who has been at the centre of a political storm in recent days, and urged people to check out a "sex tape".

"Wow, Crooked Hillary was duped and used by my worst Miss U. Hillary floated her as an 'angel' without checking her past, which is terrible!," he continued.

Mr Trump's Twitter storm came as he accused the campaign of his Democratic rival Hillary Clinton of helping 1996 Miss Universe winner Alicia Machado get US citizenship.

Mr Trump had publicly shamed Ms Machado for gaining weight, an incident that Ms Clinton referred to during the first presidential debate on Monday night.

"Did Crooked Hillary help disgusting (check out sex tape and past) Alicia M become a US citizen so she could use her in the debate?" read one tweet from from Mr Trump that was timestamped 5.30am.

The Associated Press said that Mr Trump's taunt appeared to refer to footage from a Spanish reality show in 2005 in which Ms Machado was a contestant and appeared on camera in bed with a male contestant.

The images, posted this week to a newspaper's website, are grainy and do not include nudity. The show took place almost a decade after Ms Trump invited reporters to watch Ms Machado exercise after she won Miss Universe and then gained what he's recently described as "a massive amount of weight".

With just a month before the election, Mr Trump is struggling to gain traction with women voters.

Yet the early morning Twitter blast was an insight into how the Republican candidate has seemed unable to restrain himself from veering into unhelpful territory.

Mr Trump's allies have implored him to stick to attacks on Ms Clinton over her family foundation, her emails or her long history as a political insider.

Shaming Ms Machado over intimate details from her past is particularly risky as the thrice-married Mr Trump risks calling further attention to own history with women.

Ms Clinton's campaign had no immediate formal reaction. But spokesman Brian Fallon said on Twitter: "What kind of human being is this?" 

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