Image copyright Reuters Image caption Mr Trump emphasises prosecution rates on military sexual assault are too low

Donald Trump defended a comment he made in 2013 that sexual assault in the US military happened because men and women serve alongside each other.

During a national security forum, the Republican presidential nominee said the issue was a "massive problem."

NBC Host Matt Lauer asked Mr Trump about a 2013 tweet in which he said sexual assault was to be expected when you put women in the military.

He responded the tweet was "correct," sparking an immediate backlash.

People lambasted the New York hotel developer for suggesting that the presence of women in the military was to blame for an increase in sexual assault cases.

The Pentagon released data in 2013 that found a sharp rise in reports of sexual assault in the military.

Mr Trump shared his thoughts at the time, arguing that having women in the military increased the likelihood of sexual assault.

Image copyright Twitter

Mr Lauer asked Mr Trump about his tweet during the so-called Commander-in-Chief Forum in New York.

"Well, it is a correct tweet," he told an audience of veterans. "There are many people that think that that's absolutely correct."

When Mr Lauer asked him if the solution was to remove women from the military, Mr Trump dismissed the idea but added, "something has to happen".

"Right now, part of the problem is nobody gets prosecuted."

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The New York billionaire added that his solution would be to prosecute the accused within a military court system despite the existence of an established military judicial system.

"The best thing we can do is set up a court system within the military," he said. "Right now the court system practically doesn't exist."

"When you have somebody that does something so evil, so bad as that, there has to be consequences for that person," he continued. "You have to go after that person. Right now, nobody is doing anything."

Mr Trump's answer prompted a social media firestorm, where Twitter users accused him of blaming sexual assault on gender integration in the military.

Image copyright Twitter

Image copyright Twitter

Image copyright Twitter

Mr Trump's Democratic rival Hillary Clinton was also quick to respond, quoting Mr Trump's response to Mr Lauer.

But Mr Trump's remarks are not his first on women in the military.

The businessman has previously said there were "major problems" with women serving in combat roles while noting sexual assault in the military.

"You're in there and you're fighting and you're sitting next to a woman... now they want to be politically correct. They want to do it but there are major problems," he told CBS News.

"And as you know, there are many people that think this shouldn't be done, at a high level. I can say this, the number of rapes in the military are through the roof."

A 2015 US Department of Defense study found 22% of active-duty women and seven percent of active-duty men may have experienced some form of sexual harassment last year.

Meanwhile, more than 20,000 members of the military - both men and women - reported sexual assault in 2014 and more than 160,000 reported sexual harassment or gender discrimination, according to advocacy group Protect Our Defenders.