Donald Trump is facing widespread social media backlash after he was pictured greeting supporters with a triumphant double fist pump as he arrived to a 9/11 memorial service on Tuesday, the 17th anniversary of the terror attacks.
The president, 72, along with his wife, First Lady Melania Trump, 48, were in Pennsylvania, on their way to pay their respects to the fallen heroes of United Airlines Flight 93.
The White House did not immediately respond to PEOPLE’s request for comment. In a statement ahead of Trump’s speech at the memorial event, White House press secretary Sarah Huckabee Sanders said the president’s focus for the day was “remembering the lives that were lost, and certainly honoring the individuals who were not only lost that day, but also put their lives on the line to help in that process.”
As more than one Twitter critic noted, Trump first marked Tuesday’s 9/11 anniversary “with an angry morning tweet about Russia and Hillary Clinton.”
Others criticized the tone of a tweet the president sent out on his way to the memorial event, which read, “17 years since September 11th!”
The majority of the backlash was focused on the double fist pump gesture, however, with critics saying it reflected a “lack of respect” and an “inability to feel empathy for another person’s loss.”
“This is not an exclamation point day. This is not a fist pump day,” wrote one tweeter. “You sully the solemnity of this day. History will not be kind to you.”
“Today we get a fist pump because Trump thinks ppl are there for him,” said another critic. “What a rabbit hole we have gone down. Anyone that thinks this gesture doesn’t show exactly who Trump really is, think again.”
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This is not the first time Trump has faced criticism over his reactions to 9/11.
On Sept. 11, 2001, hours after the terror attacks toppled Manhattan’s Twin Towers, killing thousands, Trump gave an interview boasting about the fact that his building at 40 Wall Street had just become the tallest in Lower Manhattan.
During the conversation with New Jersey’s WWOR-TV/UPN 9 News, the now-president commented that his building “actually was the second-tallest building in downtown Manhattan, and it was actually – before the World Trade Center – was the tallest.”
“And then, when they built the World Trade Center, it became known as the second-tallest. And now it’s the tallest,” he said at the time.
Trump has also come under fire in the past for spreading the debunked claim that Muslims in New Jersey were cheering from their rooftops as they watched the Twin Towers collapse. He also said he helped “a little bit” to clear rubble on 9/11, a claim that has been challenged by others, according to The Washington Post.