BOULDER, Colo. >> The wife and five children of the man accused of throwing Molotov cocktails at demonstrators in Boulder who were calling for the release of Israeli hostages in Gaza, injuring 12 of them, were taken into custody Tuesday by federal immigration authorities, officials said.

Mohamed Sabry Soliman, who was disguised as a gardener, had 18 Molotov cocktails and had planned to kill all the demonstrators but apparently had second thoughts, throwing just two during Sunday’s attack in which he yelled “Free Palestine,” police said. Soliman, 45, didn’t carry out his full plan “because he got scared and had never hurt anyone before,” police wrote in an affidavit.

The two incendiary devices he did throw at the group of about 20 people staging their weekly demonstration were enough to injure more than half of them, and authorities said he expressed no regrets about the attack.

Federal officials are investigating whether Soliman’s family knew about his plan, U.S. Secretary of Homeland Security Kristi Noem said in a post on X. A DHS official, speaking on condition of anonymity because they were not authorized to speak publicly on the matter, said the family was being processed by Immigration and Customs Enforcement.

Soliman — an Egyptian national who is in the U.S. illegally, according to federal officials — told authorities that no one, including his family, knew about his plans, according to court documents.

He planned the attack for more than a year and specifically targeted what he described as a “Zionist group,” authorities said in court papers, at times spelling his first name “Mohammed.”

“When he was interviewed about the attack, he said he wanted them all to die, he had no regrets, and he would go back and do it again,” Colorado’s acting U.S. attorney, J. Bishop Grewell, said during a news conference Monday.

Federal and state prosecutors filed separate criminal cases against Soliman, charging him with a hate crime and attempted murder, respectively. He faces additional state charges related to the incendiary devices, and more charges are possible in federal court, where the Justice Department will seek a grand jury indictment.

Soliman is being held on a $10 million bond. His attorney, Kathryn Herold, declined to comment Monday after a hearing where he appeared before a state judge. His next hearing is Thursday.

Soliman has been living in the U.S. illegally, having entered the country in August 2022 on a B-2 visa that expired in February 2023, Department of Homeland Security Assistant Secretary Tricia McLaughlin said in a post on X. She said Soliman filed for asylum in September 2022 and was granted a work authorization in March 2023, but that it also expired. DHS did not respond to requests for additional information.

According to an FBI affidavit, Soliman left an iPhone hidden in a desk drawer at his Colorado Springs home that contained messages to his family. After his arrest, his wife brought the phone to the local police department, saying it was his but was also used by other members of the family.

According to the affidavit, Soliman also told the police he was driven by a desire “to kill all Zionist people” — a reference to the movement to establish and protect a Jewish state in Israel.

The attack at the popular Pearl Street pedestrian mall in downtown Boulder unfolded against the backdrop of the Israel-Hamas war, which continues to inflame global tensions and has contributed to a spike in antisemitic violence in the United States. The attack happened at the beginning of the Jewish holiday of Shavuot and barely a week after a man who also yelled “Free Palestine” was charged with fatally shooting two Israeli Embassy staffers outside a Jewish museum in Washington.

Six victims hospitalized

The victims ranged in age from 52 to 88, and their injuries spanned from serious to minor, officials said.

Six victims were initially taken to a hospital, and three remained hospitalized Tuesday at the UCHealth University of Colorado Hospital on the CU Anschutz Medical Campus, hospital spokesperson Kelli Christensen said. She declined to provide information on their conditions and said they had requested privacy.

Members of the volunteer group called Run For Their Lives were attacked while holding their weekly demonstration. Video captured by witness Alex Osante of San Diego shows people pouring water on a woman lying on the ground who Osante said had caught fire during the attack.