The Federal Bureau of Investigation (FBI) is conducting an investigation into a “targeted terror attack” where several individuals were set ablaze on Sunday afternoon near Pearl Street Mall in Boulder, Colorado.

At about 4:30 p.m., the Boulder Police Department said it was responding to a report of an attack near the mall with reports of several victims. 

The incident occurred close to an event organized by “Run for Their Lives,” a grassroots group that holds global running and walking events advocating for the release of Israeli hostages held by Hamas.

Boulder Police Chief Steve Redfearn said a man is in custody, but did not release further information on the arrest.

Colorado Gov. Jared Polis in a statement on X described the attack as a “heinous act of terror.”

“I am keeping a close watch on the situation in Boulder, and my thoughts are with those injured and affected by this atrocious act of terror,” Polis stated. “Acts driven by hate of any nature are intolerable. As the details become available, the state is collaborating with local and federal law enforcement to aid this investigation.”

Israel’s Ambassador to the UN, Danny Danon, said terrorism against Jews “does not stop at the Gaza border – it is already burning the streets of America.”

“Today, in Boulder, Colorado, Jewish people marched with a moral and humane demand: to return the hostages,” Danon wrote in a statement. “In response, the Jewish protesters were brutally attacked, with an attacker throwing a Molotov cocktails at them. Make no mistake – this is not a political protest, this is terrorism. The time for statements is over. It is time for concrete action to be taken against the instigators wherever they may be.”

Colorado Rep. Joe Neguse added he is “praying hard for the victims.”

It is unclear how many people were injured, though police confirmed some were life-threatening.

Run for Their lives meets weekly in neighborhoods across the world to “quietly” address Hamas hostages, according to its website. It was started by a group of Israelis in the Bay Area in California.

Boulder police and Run for Their Lives did not immediately respond to Fox News Digital’s request for comment.

This is a breaking news story. Check back for updates.