Hamas’ attack on Israel has gripped the region in a violent and bloody conflict, the most tumultuous in decades. Now, the situation is escalating even further as Israel has ordered a siege of the Gaza Strip, the territory run by the terrorist organization.

The siege has put a halt on deliveries of food, fuel, and other essential supplies. The move comes in response to Hamas’ surprise assault on Saturday that killed 700 Israelis and nine Americans. The extremist group has also taken hundreds of hostages.

Israel’s military ordered a complete siege on the Gaza Strip on Monday, halting deliveries of food, fuel and supplies to its 2.3 million people as it pounded the Hamas-ruled territory with waves of airstrikes in retaliation for the militants’ bloody weekend incursion.

More than two days after Hamas launched its surprise attack, the Israeli military said it had largely gained control in its southern towns where it had been battling Hamas gunmen. Israel’s vaunted military and intelligence apparatus was caught completely off guard by Hamas, resulting in heavy battles in its streets for the first time in decades.

Israeli tanks and drones were deployed to guard breaches in the Gaza border fence to prevent new incursions. Thousands of Israelis were evacuated from more than a dozen towns near Gaza, and the military summoned 300,000 reservists — a massive mobilization in a short time.

The moves, along with Israel’s formal declaration of war on Sunday, pointed to Israel increasingly shifting to the offensive against Hamas, threatening greater destruction in the densely populated, impoverished Gaza Strip.

Hamas’ attack included rocket fire and ground assaults, leading to vicious street battles unseen since the 1973 Yom Kippur War. “I know you have been through terrible and difficult things. What Hamas will go through will be difficult and terrible … we have only just begun,” said Israeli Prime Minister Benjamin Netanyahu.

Israel’s Defense Minister Yoav Gallant declared, “I have given an order – Gaza will be under complete siege. We are fighting barbarians and will respond accordingly.”

The move will likely be fraught with controversy. While Israel’s actions are a direct response to sustaining a devastating onslaught from Hamas, the impoverished Gaza Strip faces a vast humanitarian crisis as the war rages on. The Gaza Health Ministry has reported hundreds of people dead as a result of Israel’s retaliation. It is worth noting that Hamas has a history of adding to the number of civilian deaths by hiding among non-combatants, using them as human shields that lose their lives when Israel retaliates.

Further complicating the matter is the threat coming from Hezbollah, a militant organization based in Lebanon. The Iran-backed group on Sunday began launching rockets and artillery fire into Israel from the north.

Nevertheless, the Israeli Defense Force (IDF) is intent on neutralizing the threat posed by Hamas.

IDF spokesperson Lt. Col. Richard Hecht said Sunday that the priority for the coming hours and days was to “control the entire enclave and kill all the terrorists in our territory.”

So far, the extent to which the United States will involve itself in this conflict is unclear. But Defense Secretary Austin Lloyd did send warships to the region to act as a deterrent against future Hamas aggression, indicating that the U.S. is set to take further action.