Hillary Clinton has pneumonia, the Democratic presidential nominee’s doctor said on Sunday afternoon, after Clinton abruptly left a 9/11 memorial ceremony in downtown Manhattan because, her campaign said, she felt “overheated” and went to recuperate at her daughter Chelsea’s luxury apartment.

“Secretary Clinton has been experiencing a cough related to allergies,” Lisa R. Bardack, Clinton’s physician, said in her statement. “On Friday, during follow up evaluation of her prolonged cough, she was diagnosed with pneumonia. She was put on antibiotics, and advised to rest and modify her schedule. While at this morning’s event, she became overheated and dehydrated. I have just examined her and she is now re-hydrated and recovering nicely.”

Video soon surfaced showing Clinton as she leaves the 9/11 event. As she waited for a van Clinton leaned against a post, then appears to buckle at the knees and stumble as Secret Service agents hold her up.

Not trying to get political today, but this Hillary Clinton video isn't a good one, assuming this is her? What the?pic.twitter.com/ffMh3lptE6

— Jason McIntyre (@jasonrmcintyre) September 11, 2016

Hillary Clinton 9/11 NYC pic.twitter.com/q9YnsjTxss

— Zdenek Gazda (@zgazda66) September 11, 2016

Clinton’s health has been an obsession of right-wing conspiracy theorists but Sunday's events have now raised her health to the level of  "legitimate campaign issue."

Hillary Clinton@9/11 NYC pic.twitter.com/ptsXzMVmMR

— Zdenek Gazda (@zgazda66) September 11, 2016