ROME (Reuters) - An Italian sports journalist said on Sunday he would take legal action after being falsely identified on social media as the suspected shooter in an assassination attempt against U.S. presidential candidate Donald Trump.

A message shared widely on the X platform reads: "Per the Butler Police Department the Trump shooter has been arrested at the scene and has been identified as Mark Violets, an Antifa member."

It was accompanied by a picture of Italian journalist Marco Violi. He is the editor of romagiallorossa.it, a fan website for the Italian soccer club AS Roma.

The FBI said early on Sunday it had identified 20-year-old Thomas Matthew Crooks of Bethel Park, Pennsylvania, as the "subject involved" in Saturday's shooting. The Secret Service said the suspect was shot dead by agents.

"I categorically deny that I am involved in this situation," Rome-based Violi wrote in an Instagram story, saying he had been woken up in the middle of the night by Instagram and X notifications related to the post.

Violi blamed two Italian X users for spreading the false information against him, and said that he would go to the police on Monday to report them and the media who picked up on their message.

Calling the X users "stalkers," Violi said he had been their target for years, and that criminal proceedings against them are ongoing. "I kindly ask to be left in peace because I have been a victim of this since 2018," he wrote.

(Reporting by Alvise Armellini; Editing by Frances Kerry)