Israel says its bombing runs are just the beginning. Next comes the ground fight.

• Israeli warplanes continue to bombard Gaza as ground forces mass in the surrounding area.
• The country's defense chief said the air attacks are just the start and would be followed by action on the ground.

Days after Israel officially declared war on Hamas following deadly attacks and atrocities, the country's continuous bombardment of the Gaza Strip has not let up. And as forces continue to mass near the border, Israeli officials continue to signal that this is just the beginning.

"We started the offensive from the air, later on we will also come from the ground," Israeli Defense Minister Yoav Gallant told soldiers near the Gaza border on Tuesday, asserting this is how the war will end. "We've been controlling the area since day two and we are on the offensive. It will only intensify."

The Israel Defense Forces (IDF) began striking what it has said are Hamas targets throughout Gaza on Saturday, immediately after the militant group carried out a series of brutal surprise attacks across the country that killed over 1,200 people — mostly civilians and some foreign nationals — and injured thousands more.

By Tuesday, the IDF said its fighter jets had hit over 2,300 Hamas targets, and this figure continues to rise as the military reported ongoing airstrikes into Wednesday evening local time. The bombardment of Gaza — a densely populated sliver of land home to roughly 2 million people — has reduced entire neighborhoods to rubble and left over 1,000 Palestinians dead and over 5,000 injured, according to health officials.

Meanwhile, hundreds of thousands of Israeli soldiers have mobilized near Gaza, alongside tanks and other heavy weaponry, as officials vow to completely crush Hamas and strip it of its military capabilities and ability to govern the enclave, which it has done for over 15 years.

In what may be preparation for a coming ground invasion, the IDF on Wednesday announced a "closed military zone" of the area surrounding Gaza to its northeast and southeast (Gaza borders Egypt to the southwest and the Mediterranean Sea to the northwest).

"Entry is strictly prohibited and constitutes a serious security risk, as well as a criminal offense," the military said. "IDF soldiers are conducting combat activity in the area and entering it endangers lives as well as harms the IDF's activities. The IDF asks the public to be alert, and not to enter the prohibited area in order to allow the security forces to continue to carry out their missions."

Any ground offensive could be a tough fight. It's been nearly a decade since Israel last invaded Gaza, giving Hamas ample time to prepare. It is also has the potential to be a very complicated battlespace.

Although Israel boasts a vastly superior military to the capabilities possessed by Iran-backed Hamas, war experts told Insider that a ground invasion would likely still leave the IDF engaged in a brutal campaign, given how difficult it is to fight in an urban environment. In Gaza, Israeli forces may be vulnerable to traps, surprise guerrilla warfare tactics, and well-armed militants who have the advantage of defending the complex terrain. Hamas could use buildings as pre-made military fortifications and leverage its elaborate network of tunnels beneath the strip.

Also complicating a potential ground invasion are the roughly 150 hostages Hamas is suspected of having abducted during the initial attacks against Israel on Saturday and the scores of civilians who remain trapped in Gaza and are scrambling to find safety after Israeli officials announced a complete siege of the enclave. United Nations officials say they're deeply concerned about the ongoing humanitarian crisis that's currently unfolding there and continue to warn against potential military escalation.

Israel, nonetheless, retains strong international support from the US in its fight with Hamas, which the US regards as a terrorist organization.

The first batch of US security assistance arrived in Israel on Tuesday, complementing the arrival of a heavily armed US Navy carrier strike group in nearby waters. The Biden administration said that the force posture changes are meant to be a signal of deterrence to other groups or militaries that may be looking to exploit the bloody crisis and join the fight. The White House said in a statement that military aid to Israel will include ammunition, interceptors for its Iron Dome, and "other defense materiel."

"Tonight the first US aircraft has landed in Israel. It carries equipment for our troops, as well as the symbol of our partnership and bond with the United States," Gallant said late on Tuesday. "This is the first of many to come."