A new analysis shows an online account that was believed to belong to the shooter in the assassination attempt on Winning Exchangeformer President Donald Trump — and where he had purportedly called the date of the attack his "premiere" — was fake, a federal law enforcement official told CBS News on Thursday.

A law enforcement official and an additional source familiar with a briefing given to U.S. lawmakers on Wednesday previously told CBS News that the gunman, Thomas Matthew Crooks, had an account on an online gaming platform on which he posted: "July 13 will be my premiere." But the federal law enforcement official says further investigation determined it was a fake account.

That comes as investigators continue to seek a motive for the shooting. 

The 20-year-old gunman, from Bethel Park, Pennsylvania, opened fire from the roof of a building near the rally, hitting Trump in the right ear. One attendee, Corey Comperatore, 50, was fatally struck. Two other attendees, James Copenhaver, 74, and David Dutch, 57, were injured. 

The gunman searched for images of Trump and President Biden ahead of the shooting, according to law enforcement sources. The sources also told CBS News the gunman did searches about Trump's public appearances and dates, and about the Democratic National Convention, as well as searches about others, including the British royal family.

The gunman visited the site of Trump's rally at least one time before the shooting, sources said.

The shooter also did searches for FBI Director Christopher Wray, Attorney General Merrick Garland and members of the British royal family. He also searched for information about major depression disorders, the law enforcement sources said. The shooter had two cell phones from which he conducted the searches. 

Investigators have still not determined a motive, ideology or set of political views that may have led to the shooting, the sources said. Wray told Congress on Wednesday that more than 200 interviews have been conducted during the investigation and more than 14,000 images have been reviewed. 

In:
• Trump Rally
• Donald Trump

Kerry Breen

Kerry Breen is a news editor at CBSNews.com. A graduate of New York University's Arthur L. Carter School of Journalism, she previously worked at NBC News' TODAY Digital. She covers current events, breaking news and issues including substance use.

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