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CNN  — 

The brazen attack by Palestinian militant group Hamas on Israel that began on Saturday will be seen as a turning point in the Palestinian-Israeli conflict with far-reaching repercussions, analysts say.

The multi-pronged attack saw as many as 1,000 assailants infiltrate Israeli territory, kill hundreds of soldiers and civilians, and take dozens of hostages back into Gaza. It was like nothing Israel had seen since the 1948 Arab-Israeli war.

Israel pledged revenge, with Israeli Prime Minister Benjamin Netanyahu vowing “mighty vengeance.” Hamas said it was prepared for all scenarios.

“Things will change forever,” said Kobi Michael, a senior researcher at the Institute for National Security Studies (INSS) in Tel Aviv. There is nothing in Israeli history that compares to this attack, he said.

“Hamas will no longer be Hamas that we knew years ago,” Michael, who previously served as the deputy director general and head of the Palestinian desk at Israel’s Ministry for Strategic Affairs, told CNN.

Hamas said the attack was retribution for what it described as attacks on women, the desecration of the al-Aqsa mosque in Jerusalem and the ongoing siege of Gaza.

Here’s what we know about the group:

What is Hamas?

An Islamist organization with a military wing, Hamas first came into being in 1987. It was an offshoot of the Muslim Brotherhood, a Sunni Islamist group that was founded in the late 1920s in Egypt.

The word “Hamas” is itself an acronym for “Harakat Al-Muqawama Al-Islamiyya” – Arabic for Islamic Resistance Movement. The group, like most Palestinian factions and political parties, insists that Israel is an occupying power and that it is trying to liberate the Palestinian territories. It considers Israel an illegitimate state.

Unlike some other Palestinian factions, Hamas refuses to engage with Israel. In 1993, it opposed the Oslo Accords, a peace pact between Israel and the Palestine Liberation Organization (PLO) that saw the PLO give up armed resistance against Israel in return for promises of an independent Palestinian state alongside Israel. The Accords also established the Palestinian Authority (PA) in the Israeli-occupied West Bank.

Palestinian Hamas militants attend the funeral of their comrade in the southern Gaza Strip in August 2017.