CNN — Israel has declared war on the Palestinian militant group Hamas after it carried out an unprecedented attack by air, sea and land on Saturday.
The large-scale surprise assault has left at least 900 dead in Israel, prompting a lethal volley of retaliatory Israeli airstrikes on Gaza that killed at least 765 people.
As they retreated into Gaza, the militants claimed to have taken at least 100 hostages with them and have threatened to kill them if airstrikes target Gaza without warning. Israel has pledged that Hamas will pay a heavy price and may now be preparing a ground incursion into Gaza.
How did the two sides get here?
Tensions between Israelis and the Palestinians have existed since before Israel’s founding in 1948. Thousands of people on both sides have been killed and many more injured over decades.
Violence has been particularly acute this year. The number of Palestinians – militants and civilians – killed in the occupied West Bank by Israeli forces since the year began is the highest in nearly two decades. The same is true of Israelis and foreigners – most of them civilians – killed in Palestinian attacks.
Israel captured Gaza from Egypt in the 1967 war, then withdrew its troops and settlers in 2005. The territory, home to some 2 million Palestinians, fell under Hamas’ control in 2007 after a brief civil war with Fatah, a rival Palestinian faction that is the backbone of the Palestinian Authority.
After Hamas seized control, Israel and Egypt imposed a strict siege on the territory, which is ongoing. Israel also maintains an air and naval blockade on Gaza. Human Rights Watch has called the territory an “open-air prison.” More than half of its population lives in poverty and is food insecure, and nearly 80% of its population relies on humanitarian assistance.
Hamas and Israel have fought several wars. Before Saturday’s operation, the last war between the two was in 2021, which lasted for 11 days and killed at least 250 people in Gaza and 13 in Israel.
Saturday’s assault occurred 50 years almost to the day since the 1973 war, when Israel’s Arab neighbors launched a surprise attack on Israel on Yom Kippur, the holiest day in the Jewish calendar, on October 6, 1973.
What is Hamas?
Hamas is an Islamist organization with a military wing that came into being in 1987, emerging out of the Muslim Brotherhood, a Sunni Islamist group that was founded in the late 1920s in Egypt.
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 and has called for its downfall.
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.
Hamas presents itself as an alternative to the PA, which has recognized Israel and has engaged in multiple failed peace initiatives with it. The PA, whose credibility among Palestinians has suffered over the years, is today led by President Mahmoud Abbas.
Hamas has over the years claimed many attacks on Israel and has been designated as a terrorist organization by the United States, the European Union and Israel. Israel accuses its archenemy Iran of backing the group.
What happens next?
Israel is now on a war footing and has already started mobilizing troops for a potential ground operation in Gaza. It has said that it will exact a heavy price on Hamas for its attack and plans to retrieve Israeli hostages from the territory.
Israel has dealt with hostage situations before, but never at this scale. In the past, militants have mostly demanded the release of prisoners held in Israeli jails in exchange for captured Israelis. In 2011, Israel traded 1,027 Palestinians for Israeli soldier Gilad Shalit, and in 2004, it released more than two dozen Lebanese and Arab prisoners – including two senior Hezbollah officials – for Elhanan Tannenbaum, an Israeli businessman and army reserve colonel, as well as the bodies of three IDF soldiers. In 2008, Israel released five Palestinian prisoners, five Lebanese prisoners and returned the bodies of nearly 200 Arab fighters in exchange for the bodies of two Israeli soldiers.
Hamas says it has taken captive 100 or more hostages. Their presence in Gaza will undoubtedly complicate any Israeli military operation there.
The militant group’s armed wing said Monday it would begin killing civilian hostages and broadcasting the act if Israel targets people in Gaza without warning.
It comes after the IDF said it planned to take control of the Gaza Strip. Its spokesperson, Lt. Col. Richard Hecht, said the aim is to “end the Gaza enclave” and “control the entire enclave.”
When asked whether it had stopped the “knock on the roof,” which is the Israeli military’s warning for civilians before it bombs a building. Hecht responded that Hamas did not “knock on the roof.”
“When they came in and threw grenades at our ambulances they did not knock on the roof. This is war. The scale is different,” Hecht said.
Senior Hamas member Saleh al-Arouri told Al Jazeera Arabic on Saturday that Hamas is ready “for all options, including a war and an escalation on all levels.”
“We are ready for the worst-case scenario, including a ground invasion, which will be the best for us to decide the ending of this battle,” al-Arouri said.
