- Senior political leader of Hamas
- Former official of the Islamic Association for Palestine
- Early leader of the Holy Land Foundation for Relief and Development
- Founder of the United Association for Studies and Research
See also: Ahmed Yassin Muslim Brotherhood Hamas
Islamic Association for Palestine
Holy Land Foundation for Relief and Development
United Association for Studies and Research
Born in 1951 in the southern Gaza city of Rafah, Mousa Mohammed Abu Marzook earned a degree in engineering from Ein Shams University (Cairo) in 1977. In 1983 he moved to the United States for a twofold purpose: to pursue a doctorate in industrial engineering (which he received in 1991), and to build—as an emissary of Sheik Ahmed Yassin—a Muslim Brotherhood infrastructure in North America.
Soon after arriving in the U.S., Marzook became affiliated with the fledgling Islamic Association for Palestine (IAP) and donated hundreds of thousands of dollars to that entity. According to a former chief of the FBI's counterterrorism department, the now-defunct IAP was, at that time, “a front organization for Hamas that engage[d] in propaganda for Islamic militants.” By the late 1980s, Marzook had become chairman of IAP’s advisory committee.
Also in the late '80s, Marzook organized the formation of the Occupied Land Fund, which later became known as the Holy Land Foundation for Relief and Development (HLF), and he provided $210,000 in seed money for the group. Moreover, in 1989 Marzook founded the United Association for Studies and Research (UASR), an Islamist think tank with ties to Hamas. According to U.S. federal prosecutors, all three organizations with which Marzook was affiliated—the IAP, HLF, and UASR—were established by the Muslim Brotherhood's Palestinian Committee in the United States “to comprehensively address Hamas' needs.”
In 1991 Marzook—while residing in Falls Church, Virginia—was elected chairman of the Hamas Political Bureau. From his Virginia base, he financed six terrorist attacks that killed a total of 47 people in Israel.
In 1992 Marzook relocated to Jordan, where he continued to play a major role in planning and coordinating terrorist attacks within Israel. He was expelled from Jordan in 1995, and on July 25 of that year he was arrested at JFK International Airport in New York for his involvement in the aforementioned acts of terrorism. Initially, American authorities sought to ship Marzook to Israel in accordance with the Jewish state's demand for his extradition, but Israel eventually dropped that demand because of “security concerns.” In 1997, therefore, the U.S. deported Marzook to Jordan, which in turn—as part of a crackdown against Hamas operatives within its own borders—expelled him to Syria in 1999.
In September 2001 the FBI raided the Texas-based computer-export company Infocom, to which Marzook had previously channeled some $250,000 in investment capital, because of its suspected ties to Hamas. On December 17 of that year, Infocom and its leaders were indicted for illegal financial dealings in which they had engaged not only with Marzook, but also with the governments of Libya and Syria. Eventually, Infocom was found guilty on all ten counts against it.
In August 2004, Marzook was indicted in the United States as a co-conspirator on racketeering and money-laundering charges related to Hamas activities dating back to the early 1990s.
After Hamas co-founder Ahmed Yassin was killed in March 2004 by an Israeli missile strike, Marzook, who resided in Syria at the time, assumed leadership of the effort to rebuild the organization's infrastructure.
In a February 2006 interview, Marzook made it clear that Israel, in his view, had no legitimate right whatsoever to exist as a nation-state. “Hamas believes that historical Palestine, that is, all of Palestine, belongs to the Palestinian people,” Marzook explained. “.... We say that all of Palestine, from the [Jordan] River to the [Mediterranean] Sea, belongs to the Palestinians.” (Click here for video of this interview.)
In the summer 2007 trial that examined evidence of the Holy Land Foundation's fundraising efforts on behalf of Hamas, the U.S. government released a list of approximately 300 of HLF’s “unindicted co-conspirators” and “joint venturers”—many of whom were affiliated with the Muslim Brotherhood and/or Hamas. Marzooks's name was on that list, along with Omar Ahmad, Abdurahman Alamoudi, Yousef al-Qaradawi, Abdallah Azzam, Jamal Badawi, Mohammad Jaghlit, Abdel Aziz Rantisi, and Ahmed Yassin. The list also included groups such as the Council on American-Islamic Relations, Hamas, Infocom, the Islamic Association for Palestine, the Islamic Society of North America, the Muslim Arab Youth Association, the North American Islamic Trust, and the United Association for Studies and Research.
Today Marzook serves as Hamas's deputy political bureau chief, operating out of Cairo, Egypt.
 Marzook is also known variously as Musa Abu-Marzuq; Sa'id Abu-Marzuq; Abu-'Umar; Mousa Mohamed Abou Marzook; Musa Abu Marzouk; and Musa Abu Marzuk.