What is Hamas? What to know about the group that launched attacks on Israel

As Israel continued to press its assault on Gaza after Hamas infiltrated by land, sea and air over the weekend, killing and capturing over 1,000 Israelis, the spotlight has focused on the militant group.

Israel's leaders have vowed retaliation, and Prime Minister Benjamin Netanyahu said Hamas "will pay an unprecedented price."

Hamas' political wing has controlled the Gaza Strip for over a decade, but the group is most known for its many suicide bombings and other attacks on Israel amid the ongoing Israeli-Palestinian conflict that has lasted decades. It's considered a terrorist group by the United States and other nations.

Here's what to know about Hamas:

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What is Hamas?

Hamas – an acronym for Harakat al-Muqawama al-Islamiya, or Islamic resistance movement – was founded in 1987 during the first Palestinian uprising against Israeli occupation of Gaza and the West Bank by a Palestinian activist connected to the Muslim Brotherhood.

In 2006, Hamas won parliamentary elections, and in 2007 the group violently seized control of the Gaza Strip from the Palestinian Authority, which was controlled by the rival Fatah movement that governs the West Bank. There have been no elections since.

The U.S. State Department designated Hamas a terrorist group in 1997. Several other nations also consider it a terrorist organization.

What is Hamas' ideology?

The group calls for establishment of an Islamic Palestinian state that would replace the current state of Israel and believes in the use of violence to carry out the destruction of Israel.

A salvo of rockets is fired by Palestinian militants from Gaza toward Israel on Oct. 10, 2023.
A salvo of rockets is fired by Palestinian militants from Gaza toward Israel on Oct. 10, 2023.

Why did Hamas attack Israel?

Up to 1,000 Hamas fighters stormed across the Israeli border by land and sea beginning at daybreak Saturday in an attack that caught Israel's military off guard.

Hamas leaders say they were pushed to attack because of an Israeli crackdown on militants in the West Bank, continued construction of settlements − which the international community considers to be illegal − thousands of prisoners being held in Israeli jails and Israel's ongoing blockade of Gaza.

Mohammed Deif, the leader of Hamas’ military wing, said “Operation Al-Aqsa Storm,” was a response to activity at the Al-Aqsa mosque compound in Jerusalem that is the third holiest site in Islam. The site, which is also located on the holiest site for Jews − who refer to it as the Temple Mount − has long been a flashpoint between Israelis and Palestinians. Israeli security services routinely raid the compound.

“Enough is enough,” Deif said in a recorded message. “Today the people are regaining their revolution.”

Who is Hamas' leader?

Deif leads the military wing while Yehia Sinwar, in Gaza, and Ismail Haniyeh, who lives in exile, are the senior leader of Hamas.

How big is Hamas' army?

Israel estimates the group has about 30,000 fighters and an arsenal of rockets and unmanned drones.

How is Hamas funded?

Hamas receives financial, material and logistical support from Iran, though so far, international leaders, including in Israel, have said there is no evidence that Iran was directly involved in Hamas’ attack.

According to the U.S. State Department, in addition to receiving funding and weapons from Iran, Hamas also raises funds in Persian Gulf countries. It receives donations from some Palestinians, and from its own charity organizations.

Hezbollah vs. Hamas

A day after Hamas launched its attack, Hezbollah also fired dozens of rockets and shells at three Israeli positions in disputed area along the country's border with Syria's Golan Heights, occupied by Israel. The attack was in solidarity with the “Palestinian resistance," Hezbollah said.

Hezbollah is a Lebanese political and militant group that's been around since the early 1980s, funded and backed by Iran and spreading Tehran's influence in the Middle East.

Like Hamas, Hezbollah is designated a terrorist group by the United States and opposes Israel, but Hamas pales in comparison to Hezbollah in terms of its terrorist capabilities. The Shiite Muslim militia has also attacked Israel with rockets in the past.

Contributing: John Bacon and Josh Meyer, USA TODAY; The Associated Press

This article originally appeared on USA TODAY: What is Hamas and why did it attack Israel? What you need to know.