Updated Saturday morning, 7:35 A.M. EDT

Israel’s long-awaited invasion of the Gaza strip is off Saturday morning to what American officials are saying is a “rolling start,” after Israel knocked out Internet and other communication in Gaza and stepped-up bombardment of the strip from the air and sea.

“Infantry, armored, engineering, and artillery forces” were  “participating in the activity, accompanied by heavy [air] fire,” the Israeli military spokesman, Rear Admiral Daniel Hagari, told reporters Saturday morning.

Explosions from continuous airstrikes lit up the sky over Gaza City for hours after nightfall Friday while early on Saturday the Israeli military released videos showing columns of armored vehicles moving slowly in open sandy areas of Gaza — the first visual confirmation of ground troops. Prior to that Israeli troops had conducted brief nightly ground incursions before returning to Israel.

Admiral Hagari confirmed that overnight two Hamas commanders, the head of the terror group’s aerial forces and a naval forces commander,  were killed in Israeli airstrikes. The incursion, which the Israel Defense Forces initially characterized only as “expanding operations” against Hamas, followed the largest bombardment of Gaza targets since the war began October 7.

“Our troops and tanks are inside the Gaza Strip. They’re shooting and they’re operating,” an IDF spokesman told the New York Times. “But our troops and tanks were inside Gaza yesterday as well,” he added.

Hamas rockets fired from northern Gaza, meanwhile, continued to rain down on Israeli settlements surrounding the strip. The terrorist group claimed that firefights took place overnight at Beit Hanoun in the northeastern part of the Strip and at the al Bureij refugee camp in the center. It was not immediately possible to confirm those claims. 

Video footage on X showed sand rising alongside heavy smoke from the air attacks, indicating that one of the IDF’s main targets was deep-dug tunnels that Hamas has  been building for years in what is widely described as a “city beneath” Gaza City.    

The announcement by the IDF signaled Israel was moving closer to an all-out invasion of Gaza, where it has vowed to crush Hamas after the terrorist group’s bloody incursion in southern Israel three weeks ago.

Israel has positioned hundreds of thousands of troops along the border with Gaza ahead of an expected ground offensive. Earlier Friday, the military said ground forces conducted their second hours-long incursion inside Gaza in as many days, striking dozens of terrorist targets over the past 24 hours.

Admiral Hagari said ground forces were “expanding their activity” Friday evening in Gaza and “acting with great force … to achieve the objectives of the war.”

Israel’s defense minister, Yoav Gallant, told foreign reporters that it “will take a long time” to dismantle Hamas’ vast network of tunnels in Gaza, adding that he expected a lengthy phase of lower-intensity fighting as Israel destroys “pockets of resistance.”

His comments pointed to a potentially grueling and open-ended new phase of the war after three weeks of relentless bombardment. Israel has said it aims to crush Hamas’ rule in Gaza and its ability to threaten Israel.

How Hamas’ defeat will be measured, though, and an invasion’s endgame remain unclear. Israel says it does not intend to rule the tiny territory of 2.3 million Palestinians but not whom it expects to govern — even as Mr. Gallant suggested a long-term insurgency could ensue.

Israel says its strikes target Hamas fighters and infrastructure and that the terrorists operate from among civilians, putting them in danger. The IDF used some of its intelligence Friday to show how Gaza’s largest medical facility, Shifa hospital, is used as a front to conceal Hamas’s military headquarters underneath it.

A UN humanitarian coordinator in the Palestinian territories, Lynn Hastings, wrote on X that without phone lines and internet, hospitals and aid operations would be unable to operate. 

The Red Crescent said it could not contact its medical teams and that residents could no longer call ambulances, meaning rescuers would have to chase the sound of explosions to find the wounded. International aid groups said they were only able to reach a few staff using satellite phones.

The IDF said that  150 underground targets in the northern Gaza Strip were destroyed during overnight strikes Friday. Those targets included terror tunnels, underground combat spaces, and additional underground terrorist  infrastructure.