BOULDER, Colo. — A man with a makeshift flamethrower yelled “Free Palestine” and threw an incendiary device into a group that had assembled to raise attention for Israeli hostages in the Gaza Strip, law enforcement officials said Sunday. Six people were injured, some with burns.

The suspect, Mohamed Sabry Soliman, 45, was expected to face charges in connection with the attack the FBI was investigating as a terrorist act.

The burst of violence at the popular Pearl Street pedestrian mall unfolded against the backdrop of a war between Israel and Hamas that continues to inflame global tensions.

The wounded range in age from 67 to 88 and the injuries spanned from serious to minor, officials said.

The attack occurred as people with a volunteer group were concluding their weekly demonstration to raise visibility for the hostages who remain in Gaza. Video from the scene shows a witness shouting, “He’s right there. He’s throwing Molotov cocktails,” as a police officer with his gun drawn advances on a bare-chested person holding containers.

— The Associated Press