Who was behind October 7, 2023 attack on Israel?
Executive summary
The October 7, 2023 attacks into southern Israel were led by the Palestinian militant group Hamas, with participation from other Gaza-based armed factions; the operation—publicly claimed by Hamas as “Operation Al-Aqsa Flood”—featured mass rocket barrages and ground incursions that killed and abducted large numbers of civilians and soldiers and triggered the wider Gaza war [1] [2] [3]. Independent bodies, governments, and human-rights organizations have attributed primary responsibility to Hamas while documenting contributions or participation by other groups and noting divergent regional political narratives about causes and culpability [4] [5] [2].
1. Who planned and claimed responsibility: Hamas as the lead actor
Multiple authoritative summaries and contemporaneous reporting identify Hamas—particularly its military wing, the Izz ad-Din al-Qassam Brigades—as the principal planner and leader of the October 7 offensive that combined thousands of rockets with armed incursions from Gaza into Israel, and which Israeli and international reporting said resulted in roughly 1,195–1,219 killed and hundreds taken hostage [1] [6] [3]. Hamas publicly announced and framed the operation in ideological and political terms that connected it to contested sites and normalization politics in the region [1] [2].
2. Other armed groups and individual operatives: a multi-group assault
Reporting and later prosecutions indicate that other Gaza-based militant groups joined or took part in the coordinated attacks alongside Hamas, and at least some attackers have been identified as members of groups such as the Democratic Front for the Liberation of Palestine’s military wing (the National Resistance Brigades), according to later arrest documents and international law-enforcement activity [7] [5]. United Nations and human-rights investigations have likewise described the assault as involving “Hamas forces and other Palestinian armed groups,” documenting systematic attacks on civilians by multiple actors that day [4] [5].
3. The scale and methods of the attack: rockets, motorbikes, and coordinated ground incursions
The offensive combined heavy rocket barrages—reported in the thousands over minutes—with daylight crossings by armed fighters on motorbikes and vehicles; witnesses and investigative bodies documented mass shootings, abductions and atrocities at civilian sites such as the Nova music festival and border communities, amplifying the human toll and the shock across Israel [1] [8] [3]. Governments and legislatures cited these operational details in classifying the incident as a large-scale terrorist assault led by Hamas [9] [10].
4. Attribution debates and geopolitical context
While the operational attribution to Hamas is broadly consistent across the sources, regional political responses diverged: some Arab and Muslim governments publicly blamed Israeli policies and occupation for creating the conditions that produced the attack, while other states and Western bodies condemned the killing and abduction of civilians and held Hamas responsible [2]. U.S. intelligence and policy reporting assessed that Iran provided material support to Hamas historically but did not orchestrate or have foreknowledge of the specific October 7 operation, illustrating limits to claims of external orchestration [10].
5. Legal, investigative, and narrative consequences
The attack prompted Israeli legislative and judicial responses—including proposals for special military tribunals to try perpetrators—and spawned international inquiries and human-rights investigations that have sought to document who did what on October 7 and the crimes committed during and after the attacks [9] [4]. Human-rights organizations have explicitly attributed war crimes and crimes against humanity to Hamas and other armed groups for acts committed during the assault and in the subsequent handling of hostages [5]. At the same time, scholarly and medical reporting that mentions the attackers sometimes uses charged descriptors—such as “fundamentalist Muslim-Arab Palestinians”—that reflect particular framings and should be read alongside other, more procedural sources [3].
6. Bottom line and evidentiary limits
The preponderance of contemporaneous public evidence and later legal and investigative work attributes primary responsibility for the October 7, 2023 attacks to Hamas, with participation by other Palestinian armed groups and individual operatives; questions about planning nodes, external support, and the precise chain of command have been partially addressed by intelligence and judicial findings but retain contested elements across political narratives and some independent inquiries [1] [7] [10] [4].