What is Hamas and why is it attacking Israel now?

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.