Who are the Leaders of Hamas’ Izz ad-Din al-Qassam Brigades?

(New York, N.Y.) – Israel has responded to the onslaught of Hamas rocket fire with a tactical campaign targeting leaders of the Iran-backed terror group in the Gaza Strip, including Mohammed Deif and Yahya Sinwar, the highest ranking Hamas officials inside Gaza. The Israel Defense Forces (IDF) has unsuccessfully targeted both Sinwar and Deif over the past two weeks.

Mohammed Deif, born Mohammed Diab Ibrahim al-Masri, is the leader of the Izz ad-Din al-Qassam Brigades, the military wing of Hamas. He has been on Israel’s “most wanted” list for more than 20 years. Deif’s mentor was Yehya Ayyash, “the engineer” renowned for building Hamas bombs and other weaponry. Israeli authorities credit Deif with masterminding al-Qassam’s rocket launching techniques, as well as the suicide bus bombings, soldier kidnappings, and tunnel-digging techniques. On May 4, 2021, Deif issued his first public statement in over seven years. In the statement, Deif stated that he was sending a “clear, final warning” that Israel would pay a “heavy price” at the hands of Hamas if Israel evicts Palestinians from their homes in Sheikh Jarrah, east Jerusalem. Hamas has launched more than 4,000 rockets toward Israeli communities since May 10. Israel has reportedly unsuccessfully targeted Deif at least twice during the past two weeks. In a sign of Deif’s influence, Ismail Ghaani, leader of the Quds Force of Iran’s Islamic Revolutionary Guard Corps, wrote to Deif this week praising Hamas and addressing Deif as a “living martyr,” a term previously applied to deceased Quds Force commander Qassem Soleimani. The IDF is reportedly continuing to target Deif.

Yahya Sinwar is a U.S.-designated senior Hamas leader with ties to the group’s political and military wings. In February 2017 internal elections, Hamas elected Sinwar as its political chief in the Gaza Strip. Sinwar replaced deputy Hamas leader Ismail Haniyeh, who replaced Qatar-based leader Khaled Meshaal in early-mid 2017 as chief of Hamas’s political bureau. Sinwar is a founding member of the forerunner of the Izz ad-Din al-Qassam Brigades. He also founded Hamas’s Majd intelligence service, which targets alleged collaborators with Israel. Sinwar won a second term as Hamas’s Gaza leader on March 10, 2021, following a contested internal election. Sinwar is the highest-ranking Hamas official in the Gaza Strip and third in the organization’s chain of command behind Qatar-based Meshaal and Haniyeh. Israel targeted Sinwar’s home in Gaza last week, but he was not present during the attack.

Additionally, the Counter Extremism Project (CEP) released a new resource on Abu Ubaida, spokesman of the Izz ad-Din al-Qassam Brigades. Ubaida is part of the brigades’ senior command and has spoken on behalf of the brigades for more than a decade. It is uncertain when Ubaida was named spokesman of the brigades. However, media sources have referred to Ubaida as the official Qassam Brigades spokesman since at least 2007. During the current conflict, Ubaida has called for all Palestinians to “rise to battle in every field.”

To read CEP’s resource Hamas, please click here.

To read CEP’s resource Mohammed Deif, please click here.

To read CEP’s resource Yahya Sinwar, please click here.

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