Donald Trump had plans to honor the anniversary of 9/11 with an appearance in the Pennsylvania town where one of the planes crashed, but he started the day very differently — by venting on Twitter about the Russia investigation.

The president’s first tweet on the 17th anniversary of the worst terrorist attack in American history by tweeting about the FBI and quoting Fox Business pundit Lou Dobbs in his defense of Trump.

“‘We have found nothing to show collusion between President Trump & Russia, absolutely zero, but every day we get more documentation showing collusion between the FBI & DOJ, the Hillary campaign, foreign spies & Russians, incredible.’ @SaraCarterDC @LouDobbs.”

Afterward, Trump re-tweeted a post from his social media director showing Trump proclaiming 9/11 as Patriot Day, a designation that first came in 2002 under President George W. Bush.

But Trump immediately went back to focusing on the Russia investigation. Just seven minutes after his 9/11 post, Trump issued another tweet about the Russia investigation, this time making reference to the now-fired FBI agent Peter Strzok, who was moved off of the Russia investigation for sending anti-Trump text messages to a woman he was dating.

New Strzok-Page texts reveal “Media Leak Strategy.” @FoxNews So terrible, and NOTHING is being done at DOJ or FBI - but the world is watching, and they get it completely. — Donald J. Trump (@realDonaldTrump) September 11, 2018

As NBC News noted, Strzok’s lawyer said that the “leak strategy” mentioned was not a plan to leak details about the Russia investigation to the media but rather a plan to prevent leaks from the investigation.

“The term ‘media leak strategy’ in Mr. Strzok’s text refers to a Department-wide initiative to detect and stop leaks to the media. The President and his enablers are once again peddling unfounded conspiracy theories to mislead the American people,” said lawyer Aitan Goelman.

This is not the first time that Donald Trump has been accused of insensitivity on 9/11. He has made a number of other questionable comments about the attacks, including an interview on the day of the attack in which he remarked that Trump Tower was now the tallest building in New York after the World Trade Center towers fell.

Trump uses 9/11 anniversary to hype his lawyer, pump up his supporters https://t.co/XpfZh4tkHO pic.twitter.com/ijxCERtjq8 — Talking Points Memo (@TPM) September 11, 2018

The Huffington Post compiled other controversial remarks Trump has made about 9/11, including a debunked claim in 2015 that he saw “thousands and thousands” of Muslims in New Jersey celebrating the attacks on the day they took place.

“I watched when the World Trade Center came tumbling down. And I watched in Jersey City, New Jersey, where thousands and thousands of people were cheering as that building was coming down,” Trump told supporters at a campaign rally. “Thousands of people were cheering.”

After his tweets on Tuesday, Donald Trump headed off to Shanksville, Pennsylvania, to make remarks honoring the anniversary of 9/11.