Former Republican presidential candidate Mitt Romney said Wednesday that he has “good reason” to believe there is a “bombshell” in Donald Trump’s taxes.

Appearing on the Fox News Channel’s “Your World With Neil Cavuto,” Romney called on each of the GOP candidates to release their previous tax documents — he then zeroed in on Trump.

“I think we have good reason to believe that there’s a bombshell in Donald Trump’s taxes,” Romney said. “I think there is something there.”

“Either he is not anywhere near as wealthy as he says he is or he hasn’t been paying the kind of taxes we would expect him to pay or perhaps he hasn’t been giving money to the vets or the disable like he has been telling us he’s been doing,” he continued. “The reason I think there is a bombshell in there is because every time he is asked about his taxes he dodges and delays and says. ‘Well, we’re working on it.’ Hey we’re not talking about the taxes that are coming due this year. We are talking about taxes already filed, back taxes.”

Romney, who noted his taxes “became a big issue” in 2012, continued to go after Trump.

“People have a right to know if there’s a problem in those taxes before they decide who our nominee should be,” he argued. “He likes to tell people how well he’s done, why isn’t he willing to let us look at the tax return?”

“There are things that could be issues and when people decide they don’t want to give you their taxes it’s usually because there’s something they don’t want you to see,” he concluded.

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