President Donald Trump criticizes his Justice Department before sending a Sept. 11, 2001, memorial message on his Twitter account.
The president also thanks Rudy Giuliani, his personal lawyer representing him in the Russia probe, for his work as New York's mayor after the attacks.
Trump is set to attend a memorial service in Shanksville, Pennsylvania, on Tuesday.
President Donald Trump began one of the most solemn days on the American calendar the way he starts many other mornings: with a tweet criticizing his Justice Department.
Tuesday marks 17 years since about 3,000 people died in the Sept. 11, 2001, attacks, the deadliest ever on American soil. The first message to come from the president's Twitter account on the somber day was a quote from a Fox Business program deflecting attention away from special counsel Robert Mueller 's Russia probe and instead toward the Justice Department and Hillary Clinton .
Only after that tweet did the president share a 9/11 memorial post from the White House director of social media, Dan Scavino, with the messages "NeverForget" and "September11th." He quickly followed that tweet up with two other Fox Business and Fox News quotes meant to criticize his Justice Department.
The White House did not immediately respond to a request to comment on the president's tweets.
The tweets preceded Trump's trip to Shanksville, Pennsylvania, where the president and first lady Melania Trump will attend a memorial for hijacked Flight 93 that crashed there on Sept. 11, 2001. Despite Trump's plans, his morning tweets reinforced a perception that he often does not recognize the gravity of national moments.
Trump has a long history of comments seen as unsympathetic on Sept. 11. On the afternoon of the attacks, he called into a radio station in New Jersey and, after a serious interview, boasted that one of his buildings was now "the tallest" in Manhattan after the World Trade Center towers collapsed.
Five years ago, Trump tweeted that he would "like to extend [his] best wishes to all, even the haters and losers, on this special date, September 11th."
Then, as a presidential candidate in 2015, he claimed he saw "thousands of thousands" of people cheering the towers' destruction in New Jersey on the day of the attack. The comments, criticized as anti-Muslim, had no basis in reality.
After his tirade Tuesday morning, Trump then thanked his personal lawyer, Rudy Giuliani , for doing a "GREAT job" as New York's mayor after the attacks. He called Giuliani, who represents him in the Russia investigation, a "TRUE WARRIOR!"
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Watch: Flag is unfurled at the Pentagon to mark 9/11
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