In a significant move towards holding Hamas accountable for the deadly attacks of October 7, the U.S. Department of Justice has announced federal terrorism charges against Yahya Sinwar, the mastermind behind the attack, and five other senior Hamas officials. The charges come nearly a year after the massacre, which resulted in the deaths of over 1,000 civilians, including more than 40 American citizens.

U.S. Attorney General Merrick Garland issued a statement on Tuesday, emphasizing the gravity of the charges. “The Justice Department has charged Yahya Sinwar and other senior leaders of Hamas for financing, directing, and overseeing a decades-long campaign to murder American citizens and endanger the national security of the United States,” Garland said. He also vowed continued efforts to bring Hamas to justice, stating, “These actions will not be our last.”

The criminal complaint, unsealed in the Southern District of New York, outlines seven charges against the Hamas leaders, including conspiracy to murder U.S. nationals, conspiracy to provide material support for terrorism, and conspiracy to use weapons of mass destruction resulting in death.

The charges are based on an extensive counterterrorism investigation led by FBI Special Agent Paula Menges, which traces Hamas’s terrorist activities back to the organization’s founding mission to eradicate the state of Israel. The complaint details how Hamas’s violent acts, including attacks dating back to 1996, have claimed the lives of numerous U.S. citizens.

The October 7 attack, described in the complaint as Hamas’s “most violent, large-scale terrorist attack to date,” saw over 2,000 armed fighters infiltrate Israeli towns and farms, leading to the massacre of over 1,000 people and the kidnapping of more than 200 others. The complaint also highlights the sexual violence, rocket attacks, and other brutal tactics employed by Hamas during the assault. The Justice Department confirmed that 43 American citizens were killed in the attack, with at least ten more taken hostage or still missing.

The complaint also reveals the support Hamas received from the Iranian regime and Hezbollah, which enabled the group to carry out the October 7 attack. It details how Iran’s Revolutionary Guard Corps provided financial backing, training, weapons, and other supplies to Hamas, furthering Iran’s strategy of surrounding Israel with armed proxy groups.

Among the indicted leaders, Hamas political leader Ismail Haniyeh died in July during a visit to Iran, and another key figure, Mohammed Deif, was reportedly killed by an Israeli airstrike last month. However, Hamas has not confirmed Deif’s death.

The charges follow the recent death of Israeli-American hostage Hersh Goldberg-Polin and five others, whose bodies were discovered in a tunnel beneath Rafah, Gaza. Goldberg-Polin was among those kidnapped during the October 7 attack at the Nova music festival.