More than a year after President Barack Obama released a copy of his long-form birth certificate, real estate mogul Donald Trump is still not convinced.

Trump took to Twitter on Monday, introducing fresh fuel to the birther movement.


Donald J. Trump
An 'extremely credible source' has called my office and told me that 's birth certificate is a fraud.

Back in April 2011, the White House released the document, showing that Obama was born on Aug. 4, 1961 in Honolulu's Kapiolani Maternity and Gynecological Hospital.

"I know that there is going to be a segment of people for which no matter what we put out, this issue will not be put to rest," Obama said. "But I am speaking for the vast majority of the American people as well as for the press. We do not have time for this kind of silliness. We have better stuff to do. I have got better stuff to do. We have got big problems to solve."

By May 29, 2012, Trump said in a CNBC phone interview that the document was not enough, and that "nothing has changed my mind." In a CNN interview on the same day, the "Celebrity Apprentice" host continued to press the issue, prompting Wolf Blitzer to say Trump was "beginning to sound a little ridiculous."

White House Press Secretary Jay Carney slammed Trump's efforts the following day, calling it a "ridiculous distraction" from real issues.

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