Gaza - Hamas has seen its forces halved over eight months of warfare, relying increasingly on insurgent tactics to thwart Israel’s control over Gaza, according to U.S. and Israeli officials.

The group, which once had an estimated 20,000-25,000 fighters, now has between 9,000 and 12,000, three senior U.S. officials reported. Israel, in contrast, has lost nearly 300 troops in the Gaza campaign. As Israeli forces advance toward Rafah, Hamas has shifted from direct confrontations to ambushes and improvised explosive devices (IEDs), often targeting behind enemy lines.

Wissam Ibrahim, a Gaza resident, confirmed the change in tactics: "Earlier, Hamas fighters would engage Israeli troops directly. Now, they wait for deployment before launching ambushes."

U.S. officials, who spoke on condition of anonymity, suggested these tactics could prolong the insurgency, supported by smuggled and repurposed weapons. Israeli Prime Minister Benjamin Netanyahu's national security adviser indicated the conflict could extend into late 2024.

In a propaganda effort, Hamas fighters have been posting videos of their ambushes on social media.

Peter Lerner, an IDF spokesperson, acknowledged the shift in Hamas tactics and stated that completely eradicating Hamas fighters and tunnels is not realistic. "Destroying Hamas as a governing authority is an achievable military objective," he said.

Amid pressure from Washington for a ceasefire, the war, which started on October 7 when Hamas attacked southern Israel, has resulted in over 1,200 Israeli deaths and more than 250 hostages. Gaza has been devastated, with over 36,000 fatalities, according to Palestinian health authorities, and the UN reporting over a million people facing severe hunger.

Approximately 7,000-8,000 Hamas fighters are reportedly entrenched in Rafah. Key leaders, including Yahya Sinwar, his brother Mohammed, and Mohammed Deif, are believed to be hiding in tunnels with Israeli hostages.

A U.S. administration official noted Hamas's ability to rapidly withdraw and regroup. Lerner confirmed the protracted nature of the conflict, citing the extensive network of tunnels, known as the Gaza metro, used by Hamas.

Israel recently claimed control of the Gaza-Egypt land border to stop weapons smuggling, uncovering about 20 tunnels. Egypt’s State Information Service has not responded to Israel’s claims, though Egyptian officials have previously denied such smuggling activities, stating they destroyed the tunnels years ago.