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Hillary Clinton left the New York City memorial marking the 15th anniversary of the September 11, 2001, terror attacks after becoming "overheated," her campaign said.
Nick Merrill, a campaign spokesman for Clinton, said in a statement that the Democratic presidential nominee felt "overheated" and "departed to go to her daughter's apartment."
Clinton was "feeling much better," Merrill added.
Fox News first reported that Clinton suffered a "medical episode" and possibly fainted as she was helped into a vehicle and rushed from the scene.
A witness told Fox that Clinton lost a shoe during the incident.
MORE ON #HILLARY per witness: "unexpected early departure"; she stumbled off curb, "knees buckled", lost a shoe as she was helped into van
- RickLeventhalFoxNews (@RickLeventhal) September 11, 2016Two senior law enforcement sources told NBC News that Clinton became ill and may have fainted at the scene.
Two senior law enforcement sources tell NBC News that Hillary Clinton fell ill and may have fainted at the 9/11 Memorial.
- Kyle Griffin (@kylegriffin1) September 11, 2016PIX 11 News, a local New York City outlet, also reported that Clinton fainted.
Reporters who travel with Clinton were met with radio silence from her campaign for approximately 45 minutes after the former secretary of state was said to have left the memorial.
Clinton left the 9/11 ceremony 30+ mins ago but press pool was not told to where. Aides now not responding to any Qs about her whereabouts
- Liz Kreutz (@ABCLiz) September 11, 2016Republican presidential nominee Donald Trump, addressing a reporter's question as he departed the memorial, said he "didn't know anything about" Clinton's health issue.
For weeks, conservative news outlets have promoted stories suggesting Clinton is secretly battling health issues. The Clinton campaign has strongly denied such claims and dismissed them as conspiracy theories.