Mohammed Deif

Overview

Mohammed Deif, born Mohammed Diab al-Masri in 1965, was a senior leader of Hamas, a terrorist organization, and commander of its military wing, the Al-Qassam Brigades. He became involved with Hamas during the First Intifada, which began in 1987, and rose through its armed apparatus. From 2002 until his death in 2024, he held command of the Brigades. He was also Hamas’s second-in-command in Gaza. His career encompassed suicide bombings, kidnappings, rocket attacks and the development of Hamas’s military capabilities in Gaza. He spent decades evading Israeli forces while remaining a central figure in the organization’s operations. [1][2][11][12]

Deif and Yahya Sinwar coordinated the planning of the October 7 attacks against Israel. On October 7, 2023, Hamas terrorists crossed from Gaza into southern Israel, massacred 1,200 people and abducted 251 hostages into Gaza. Deif announced the assault in a recorded address under the name Operation al-Aqsa Flood and urged further attacks inside Israel. Israeli fighter jets killed him and Khan Yunis brigade commander Rafa’a Salameh in a strike near Khan Yunis on July 13, 2024. Israel confirmed Deif’s death on August 1; Hamas formally acknowledged it in January 2025. [1][4][8][14][15]

Early life

Deif was born Mohammed Diab al-Masri in 1965 in the Khan Yunis area of southern Gaza. Accounts of his early years place him in the Khan Yunis refugee camp. He studied science at the Islamic University in Gaza, including physics, chemistry and biology. His involvement with Hamas began amid the First Intifada in 1987, when the organization emerged as a force in Gaza. His entry into Hamas during that period began a long career within its armed network. [4][11][12]

His adopted name, Deif, means “guest” in Arabic. It reflected his practice of moving between locations to avoid being found by Israeli forces. That practice became central to his public image: for years he appeared rarely, issued few statements and remained difficult to locate. Secrecy also helped him retain command despite repeated Israeli attempts to kill him. The name conveyed his movement from one temporary refuge to another while he directed Hamas operations in Gaza. [4][11]

Career

Deif rose through Hamas as its armed wing carried out attacks against Israelis during the 1990s. He helped plan and carry out suicide bombings, including attacks on buses in Jerusalem, and became one of Israel’s most-wanted terrorists in 1995. His role extended into bombings in the early 2000s. Sinwar and Deif were behind mid-1990s suicide attacks that killed dozens of Israelis. Their relationship, formed in Khan Yunis, developed into a lasting military partnership. Deif was a former commander and mentor to Sinwar, who later served as his representative on the ground in Gaza. [11][12][13]

Israel also sought Deif over Hamas kidnappings and killings. His rise within the armed wing followed years of attacks, including the 1994 kidnapping and killing of Israeli soldier Nachshon Wachsman and the dispatch of bombers to Jerusalem buses in 1996. These operations established his standing among Hamas commanders and made him a priority target for Israeli security forces. His continued involvement after surviving Israeli strikes gave him an unusually long tenure in an organization whose senior military figures were repeatedly targeted. [11][12][13]

In 2002, after the death of his predecessor Salah Shehadeh, Deif became commander of the Al-Qassam Brigades. The post placed him at the head of Hamas’s military wing in Gaza. He oversaw an organization that used bombs, rockets, tunnels and armed units against Israel. Marwan Issa served as his deputy. Deif’s authority extended beyond individual attacks: he directed military planning, helped develop the Brigades’ capabilities and remained a senior figure in Hamas’s Gaza leadership for more than two decades. [1][3][11][12]

Deif survived at least six Israeli attempts to kill him before 2024. An Israeli strike in 2002 injured him, but he remained alive and retained his place in Hamas’s command structure. In 2003, he escaped an Israeli Air Force strike on a meeting attended by senior Hamas figures, including Ahmed Yassin and Ismail Haniyeh. During the 2014 Gaza war, an Israeli airstrike targeting him killed his wife and at least one of his children. Israeli intelligence subsequently assessed that he had survived and returned to active involvement with the military wing. His survival over successive wars strengthened his symbolic status among Hamas supporters while leaving him an enduring Israeli target. [4][12][13]

In 2015, the United States designated Deif a Specially Designated Global Terrorist. Sinwar received the same designation that year. The designation came after decades in which Deif had been associated with attacks on Israeli civilians and with Hamas’s military command. It also reflected his position within an organization that continued to build armed capabilities in Gaza despite losses among its leadership. [4]

Sinwar’s difficult victory in Hamas’s March 2021 leadership election preceded renewed cooperation with Deif and the military wing. During tensions in Jerusalem that year, Deif issued an ultimatum to Israel. Hamas used events around Damascus Gate and the Temple Mount, alongside riots in Sheikh Jarrah and Silwan, as the setting for its threat. Sinwar launched a rocket barrage against Israel to implement the ultimatum. Deif’s public intervention and the subsequent rocket fire showed how Hamas’s political and military leadership acted together during the escalation. [16]

Sinwar again enlisted Deif ahead of Jerusalem’s Flags March in May 2022 as Hamas sought to influence Israel’s plans. Their partnership carried into the planning of October 7. Deif commanded the armed wing that would execute the assault, while Sinwar led Hamas in Gaza. The two men’s positions gave them control over different parts of the organization, linking military preparation to decisions made by Hamas’s Gaza leadership. [7][14]

Ideology and statements

Deif’s public statements were rare, but those he issued called for violence against Israel. His 2021 Jerusalem ultimatum threatened consequences if Israel did not meet Hamas’s demands. Hamas then fired rockets toward Israel. The episode made Jerusalem a focus of Hamas’s armed campaign and placed Deif’s warning at the center of its public messaging. It also showed the significance Hamas assigned to a statement from a commander who ordinarily kept himself out of public view. [16]

On October 7, 2023, Deif announced Hamas’s attack in an audio recording under the name Operation al-Aqsa Flood. He urged attacks on Israelis with guns, knives, Molotov cocktails and vehicles. He also called on Arabs inside Israel to “kill, burn, destroy, and shut down roads.” His message sought to extend the violence beyond the Hamas units already attacking southern Israel. Al Jazeera broadcast his call within hours of the start of the assault, giving his announcement an audience during the massacre itself. The recording tied Deif publicly to the operation that Hamas’s armed wing had prepared and launched. [4]

Supporters later used Deif’s image and name in demonstrations and media. At anti-Israel protests in New York in May 2024, signs displayed him alongside Sinwar and Al-Qassam Brigades spokesman Abu Obaida. Demonstrators outside Israel’s embassy in Amman, Jordan, chanted Deif’s name and declared themselves his people. These displays reflected the prominence Hamas supporters gave him as a military symbol. They did not change his responsibility as a commander who directed attacks on civilians and hostage taking. [6][8]

Role in attacks or conflicts

Deif’s role in Hamas’s attacks began long before October 7. The bus bombings of the 1990s and early 2000s were among the operations that brought him to the top of Israel’s wanted list. Those attacks struck civilian transportation and killed Israelis. His work on Hamas’s military capabilities also gave the organization means to conduct sustained attacks from Gaza. As commander, he presided over the Brigades through repeated confrontations with Israel and through the expansion of its armed infrastructure. [11][12][13]

His partnership with Sinwar became especially consequential after 2021. The Jerusalem ultimatum connected Deif’s threat to a Hamas rocket barrage ordered by Sinwar. Their cooperation continued as Hamas prepared a much larger assault. Deif coordinated with Sinwar in planning October 7 and helped plan and execute the massacre and hostage abductions. Marwan Issa, Deif’s deputy, was another senior figure in the armed wing during this period. Together, the Hamas leadership and military command organized an attack that combined mass killing in Israeli communities with the seizure of hostages for transfer into Gaza. [1][3][4][7]

On the morning of October 7, 2023, Hamas terrorists breached the border from Gaza and attacked communities, military positions and civilians in southern Israel. The massacre killed 1,200 people; 251 hostages were abducted into Gaza. Deif’s recorded announcement followed the start of the assault. In it, he identified the operation and urged others to join attacks inside Israel. His command position, coordination with Sinwar and public announcement made him one of the principal figures behind the operation. The attacks triggered the Gaza war and Israel’s campaign against Hamas’s leadership and military wing. [1][4][7][14]

Hamas’s planning and its public presentation of the massacre served different purposes. Preparation required coordination inside its military apparatus; Deif’s broadcast presented the violence as an operation for supporters to join. His instructions named weapons and methods available to individuals beyond the units that had crossed from Gaza. By calling for attacks inside Israel while people were being murdered and abducted in the south, Deif sought to widen the assault. His words also provide a direct record of his endorsement of the violence that day. [4]

The International Criminal Court prosecutor, Karim Khan, sought an arrest warrant for Deif on May 20, 2024, along with applications concerning Sinwar and Ismail Haniyeh. The court issued a warrant for Deif on November 21, 2024, after the Israeli strike that had killed him but before Hamas acknowledged his death. The proceedings concerned alleged war crimes and crimes against humanity connected to the October 7 attacks. A warrant was a judicial step in those proceedings, not a criminal conviction. [10][15]

Death or current status

On July 13, 2024, Israeli fighter jets struck a compound near Khan Yunis where Deif and Rafa’a Salameh, commander of Hamas’s Khan Yunis brigade, were located. The strike killed both men. On August 1, the Israel Defense Forces and the Israel Security Agency confirmed Deif’s death following an intelligence assessment. At the time, he was the highest-ranking Hamas leader killed in Gaza since the war began. His death removed the commander who had led Hamas’s armed wing for more than two decades and helped direct its October 7 assault. [1][14]

Hamas did not formally acknowledge Deif’s death until January 30, 2025, more than six months after the strike. Its announcement also confirmed deaths of other senior military figures, including his deputy Marwan Issa and Salameh. The delay meant the International Criminal Court had issued its November warrant while his death had not yet been formally acknowledged by Hamas. On February 26, 2025, after receiving confirmation of his death, the court rendered the warrant ineffective and terminated proceedings against him. The termination followed his death; it did not resolve the underlying accusations through a trial. [10][15]

Izz al-Din al-Haddad took command of the Al-Qassam Brigades after Deif’s death. His succession demonstrated that the organization retained a command structure, although it had lost a leader with extensive operational experience. Deif’s removal compounded damage to Hamas’s military wing during the war. It did not, by itself, end Hamas’s ability to fight, and the organization continued to operate while shifting toward guerrilla warfare. [7][9]

Legacy

Deif’s legacy rests on his long command of Hamas’s armed wing and his responsibility for attacks on Israelis. The bus bombings associated with his rise, the rocket threats he issued in 2021 and the October 7 massacre mark distinct periods of that career. His repeated survival of Israeli strikes made him a symbol for Hamas supporters, while his secrecy and operational knowledge gave him practical value to the organization. His death deprived Hamas of both a senior commander and a figure it had used to represent its military campaign. [4][9][11][13]

Hamas continued to commemorate him after acknowledging his death. In July 2025, the Al-Qassam Brigades circulated a memorial post honoring Deif as its deceased chief of staff. His image also appeared in anti-Israel protest material, and a song with more than 2.3 million listens used his silhouette and Hamas imagery while glorifying the October 7 attacks. Such uses of his image show how the organization and its supporters sustained his symbolic role after his death. They also show why his killing, although a major blow to Hamas’s leadership, could not alone erase the networks or narratives he helped build. [5][6][9]