WATCH: Hillary Clinton Stumbles While Leaving 9/11 Ceremony

A video showing Hillary Clinton stumbling before getting swept away in a black van has people wondering about the Democratic Presidential candidate’s health.

According to Rick Leventhal, Clinton made an “unexpected early departure.” As she was helped into a van, her “knees buckled” and she lost one of her shoes.

Leventhal also quoted a witness who said that Clinton was “clearly having some type of medical episode.”

Fox News said in a report on their website that a law enforcement source said that Clinton left because “she wasn’t feeling well.”

Speaking live on the network, Leventhal said:

She unexpectedly left early because of what appeared to be a medical episode. I have a law enforcement source who was there, who was 15 feet away from Hillary Clinton. He said she was standing on a curb with her protective detail waiting for her motorcade.

They were surprised to see her because she wasn’t meant to be leaving yet… When it finally rolled up my source said she stumbled off the curb, appeared to faint, lost one of her shoes, which wound up underneath the van…

The protective detail helped her into the van and the van took off, presumably in the direction of the hospital.

ABC News’ Liz Kreutz said that the press pool who were at the event were not told where Clinton was going and that aides were not responding to questions. That report was reiterated by NBC News’ Monica Alba.

Later, Clinton’s campaign put out a statement reading:

Secretary Clinton attended the September 11th Commemoration Ceremony for just an hour and thirty minutes this morning to pay her respects and greet some of the families of the fallen.

During the ceremony, she felt overheated so departed to go to her daughter’s apartment, and is feeling much better.

Watch the video of her departure above.

It has since been reported that Clinton is suffering from pneumonia, too.