A man accused of a firebomb attack that killed one person and injured a dozen others during a demonstration last year in Boulder, Colorado, in support of Israeli hostages in Gaza was scheduled to plead guilty Thursday to murder and other charges.

Mohamed Sabry Soliman faces up to life in prison without the possibility of parole for the attack in downtown Boulder last 1 June.

Soliman’s attorneys revealed he would plead guilty in a recent court filing in a related federal case. He was set to appear Thursday before a state district judge, Nancy Salomone, to do so.

Soliman has pleaded not guilty in federal court to hate crime charges and prosecutors have been weighing whether to seek the death penalty in the federal case, according to his attorneys.

Soliman initially pleaded not guilty in state court to murder and dozens of attempted murder and assault charges for throwing two Molotov cocktails at demonstrators at a pedestrian mall in downtown Boulder, a city of 100,000 people north-west of Denver that’s home to the University of Colorado.

An 82-year-old woman who was injured in the attack later died. A dozen others also were injured.

Soliman is an Egyptian national who federal authorities say was living in the US without documentation. Investigators allege he planned the attack for a year and was driven by a desire “to kill all Zionist people”.

Tara Winer, Boulder’s mayor pro tem, said the attack was horrific and victims included close friends.

Soliman had been living with his family in a two-bedroom apartment in Colorado Springs – about 97 miles (156km) away – at the time of the attack. He had moved to the US from Kuwait in 2022 with his wife and their five children and worked in a series of low-paying jobs.

The couple divorced in April.

Investigators allege Soliman told them he intended to kill the roughly 20 participants at the weekly demonstration at Boulder’s Pearl Street pedestrian mall. He threw two of more than two dozen Molotov cocktails he had with him while yelling, “Free Palestine!”

Federal prosecutors allege the victims were targeted because of their perceived or actual connection to Israel. Soliman’s federal defense lawyers argue he should not have been charged with hate crimes because he was motivated by opposition to Zionism, the political movement to establish and sustain a Jewish state in Israel.

An attack motivated by someone’s political views is not considered a hate crime under federal law.