A message sent out by Donald Trump's Twitter account Sunday morning was deleted soon after appearing.

"I would like to extend my best wishes to all, even the haters and losers, on this special date, September 11," the message read.

The tweet, originally from 2013, was re-posted to the Republican presidential candidate's account Sunday morning. New features from Twitter allow users to retweet or quote tweet themselves, actions that can be used to resurface older ideas.

Critics argued against Trump's use of the word "special," contending the word has a positive connotation and therefore offended Americans who were affected by the tragedy.

Trump later posted a lengthy note on Facebook, saying, "Today, we mourn for all the lives lost. We mourn for all the children who had to grow up without a mom or dad, and for all the parents who've had to struggle on without their children."

Trump attended a 9/11 memorial service in New York Sunday morning.

Clinton attended the same event, but the Democratic presidential candidate left early. Video showed Clinton stumbling before being helped into a vehicle, and her campaign spokesman later said she was "overheated."

Clinton was later seen seen leaving her daughter's New York apartment, saying, "I'm feeling great."