AUSTIN, Texas — A Massachusetts man filed a defamation lawsuit Monday against right-wing radio host and conspiracy theorist Alex Jones and his Texas-based InfoWars website, alleging they falsely identified him as the gunman who killed 17 people at a Florida high school on Feb. 14.

In a complaint filed in a state district court in Austin, Marcel Fontaine said InfoWars posted his photograph on its website the day of the shooting, depicting him as the Marjory Stoneman Douglas High School gunman and labeling him a ‘‘commie’’ supported by the Islamic State group.

However, Fontaine said he lives in Massachusetts and has never been to Florida. His attorneys claim InfoWars targeted him because of a novelty T-shirt depicting intoxicated Communist Party figures. The InfoWars article was redistributed by numerous right-wing websites.

Florida authorities have charged Nikolas Cruz with capital murder in the school shooting.

Fontaine’s attorneys described Jones’ career as ‘‘recklessly opportunistic’’ for the ways he misleads his listeners.

‘‘Mr. Jones feeds his audience a steady diet of false information intended to convince them that a shadowy association of global elites are hatching countless insidious schemes to destroy their way of life or threaten their bodily fluids,’’ the 22-page complaint states.

Fontaine demanded a correction on Feb. 26, but Jones and InfoWars did not respond.

Fontaine ‘‘continues to suffer harassment and peril even from individuals aware of his identity as a Massachusetts resident but who nevertheless remain convinced he was part of a horrifying conspiracy,’’ his attorneys said.