The Washington Post reported on Saturday that Hamas leader Yahya Sinwar had been preparing for a large-scale attack against Israel for months before the October 7 operation, also known as Operation al-Aqsa Flood.

According to sources who met with Sinwar in early 2023, he hinted at a significant plan, although no specific details were provided at the time.

The WashPo report reveals fresh insights into how Hamas, under Sinwar's leadership, meticulously organized the operation, amassing weapons and constructing an intricate network of underground tunnels within Gaza.

Despite years of isolation in the densely populated strip, Hamas developed a sophisticated arsenal of homemade rockets and improvised explosive devices.

The report, however, alleges that the Resistance relied on external financial support and training from Iran, though these claims have yet to be fully verified due to a lack of substantial evidence.

It also suggests that a significant portion of Hamas' resources were reportedly siphoned from aid funds, charitable donations, and local tax revenues.

Read more: 'Israel' knows nothing about Hamas' tunnels: Released captive

Hamas’s vast underground tunnel system, often referred to as the "Gaza metro," enabled the movement of weapons and fighters out of sight of Israeli surveillance.

Israeli occupation forces (IOF) officials were reportedly shocked by the tunnel network’s scale, which spanned hundreds of miles with bunkers and passages reaching up to 120 feet below ground.

The tunnel system not only facilitated the October 7 operation but has also allowed Hamas to continue fighting despite "Israel’s" intense military response and the heavy losses incurred.

The WashPo investigation, based on interviews with military and intelligence analysts as well as Palestinian officials, shows how Hamas became largely self-sufficient, producing up to 80 percent of its weapons locally.

Sinwar's strategic shift focused on ensuring Hamas could function without substantial external aid, allowing it to sustain its resistance throughout a prolonged war.

Read more: IOF ops. in Gaza reveal Hamas' 'vast, complicated' tunnel network: NYT

Even after losing thousands of fighters and several key commanders, Hamas remains active.

The tunnel network has been essential to the group’s survival, but cash reserves and resources are reportedly dwindling, and humanitarian conditions in Gaza have deteriorated drastically, with thousands of civilians dead and much of the territory in ruins.

Despite these setbacks, Hamas’s recruitment efforts remain strong, driven by revenge and anger among young Palestinians.

The report highlights growing concerns among Israeli and international officials that Hamas, though weakened, could rebuild and continue posing a serious threat.

Its survival strategy, which includes locally produced weapons and an extensive tunnel network, has prompted a reassessment of how "Israel" and its allies approach the ongoing conflict.

As the war enters a new phase, experts warn that Hamas may shift to insurgency-style tactics, including the use of IEDs and guerrilla warfare, potentially posing a long-term challenge for Israeli forces invading Gaza.