An Israel Air Force strike in Gaza on Thursday killed Hamas' Interior Minister Said Sayyam, one of the Islamist militant group's three most senior leaders in the coastal strip.
A Hamas official vowed vengeance for Siam's death. "The blood of Said Sayyam will be a curse on the Zionist entity," Mohammed Nazzal told Al-Jazeera television.
Sayyam, 50, was killed in an air strike that targeted the home of his brother Iyad. Also killed in the attack were his son, his brother, as well as Salah Abu Shreich, head of internal security in the organization and the person responsible for the liaison between the political and military wings of Hamas.
Palestinian sources said Hamas' military commander in Gaza City, Mahmoud Watfah, was also killed in the attack.
Six other Hamas operatives were wounded in the air strike in the heart of Gaza City, the sources said. The IDF Southern Command ordered the airstrike on the basis of precise intelligence provided by the Shin Bet security service.
Sayyam was the effective founder of the Hamas-led police force. He pushed for Hamas' bloody 2006 coup in Gaza, during which it ousted the rival Fatah faction from power.
As interior minister in Hamas' government in Gaza, Sayyam oversaw thousands of security agents and was widely feared. He was the number three behind Ismail Haniyeh and Mahmoud Zahar, and was seen by many as the most extreme of the triumvirate.
The air strike on Sayyam was apparently an attempt by Israel to deliver an image of victory in its offensive against Hamas. The Israel Defense Forces understands that Hamas' agreement in principle to the Egyptian proposal for a cease-fire in Gaza signals that the campaign is nearing its end.
In an interview with Haaretz in November 1995, Sayyam said, "I do not hate [Israelis] for being Jewish or Israeli but because of what they have done to us. Because of the acts of occupation."
In response to a question about whether he saw a chance for change in relations between Palestinians and Israelis, he said, "It is difficult to forget what was done to us. If the reason for the hate will not exist, everything is possible.
"But if the reason remains, it is impossible to love. First we must convince in general and in principle that we have been wronged, then we can talk about '67 or '48. You still do not recognize that we have rights. The first condition for change is recognition of the injustice we suffered."
Bradley Burston contributed to this report
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