By Gareth Vipers, Jack Morphet and Victoria Albert

The man accused of carrying out a flamethrower attack in Boulder, Colo., on Sunday was in the U.S. on an expired visa, according to the Department of Homeland Security.

The suspect, Mohamed Sabry Soliman, entered the U.S. in August 2022 on a B2 visa, department spokeswoman Tricia McLaughlin said in a post on X. That visa, typically used for tourism, expired in February 2023, she said, adding that he had filed for asylum in September 2022.

All eight victims of the attack are alive and remain in the hospital, police said.

"Immigration security is national security," White House Deputy Chief of Staff Stephen Miller said on X. "No more hostile migration. Keep them out and send them back."

The man suspected of the attack, which unfolded in the city's busy downtown area Sunday afternoon, was arrested at the scene and later charged with first-degree murder. Authorities didn't give any further information.

Soliman was heard shouting "Free Palestine" as he used a makeshift flamethrower and threw an incendiary device on a group advocating for the release of hostages being held by Hamas, the authorities said.

The incident occurred around 1:30 p.m. local time near the courthouse in a pedestrian area crowded with people, Boulder Police Chief Stephen Redfearn said.

The police believe the suspect -- age 45 and from El Paso county -- was working alone. Soliman's bail was set at $10 million, according to the Boulder County Sheriff's Office.

Run for Their Lives, a group that aims to bring attention to the hostages taken from Israel by Hamas, was holding a regular event at the Pearl Street Mall when the attack occurred.

Group member Jean Unger told The Wall Street Journal that the Boulder chapter of the organization follows the same route for what it calls "peace walks."

Unger said it isn't unusual for the group of 25 to 30 participants to cross paths with protesters, but the walkers don't engage with them, Unger said. When she heard shouting of "Free Palestine," she didn't pay immediate attention.

"Next thing I saw was big flames, from behind me. There was a woman on fire, and people rushing to try and help her, and other people had flames on their legs," Unger said. She said several members in her group were injured, including one who is a Holocaust survivor.

Four women and four men, ranging in age 52 to 88, were being treated at hospitals, authorities said.

Federal Bureau of Investigation director Kash Patel said on Sunday that the agency was investigating the incident as a targeted terrorist attack.

Anxiety about violence in the U.S. stemming from the Hamas-Israeli conflict has been high since last month, when a man who also shouted "Free Palestine" fatally shot two Israeli Embassy staffers near a Jewish museum in Washington.

"This is the second violent attack on the U.S. Jewish community in two weeks," said Anti-Defamation League Chief Executive Jonathan Greenblatt. "Two peaceful Jewish events that ended with rage-filled, violent attacks."

Write to Gareth Vipers at gareth.vipers@wsj.com, Jack Morphet at jack.morphet@wsj.com and Victoria Albert at victoria.albert@wsj.com

(END) Dow Jones Newswires

June 02, 2025 11:55 ET (15:55 GMT)

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