Israeli forces have neared the centre of Gaza City, as Hamas fighters reportedly regroup amid fears of intense street-to-street fighting.
Thousands of Palestinians have been forced to flee the city since Israel launched its ground offensive last week.
Israel describes the city as the last stronghold of Hamas and says its aim is to eliminate terrorists and rescue its 48 remaining hostages, 20 of whom are thought to be alive.
The BBC has verified footage of an Israeli tank at Hamid Junction, around 1.5km (0.9 miles) from the central al-Shifa hospital. Israeli armoured vehicles were also reportedly seen close to the main UN compound in southern Gaza City, about 700m (2297ft) from the centre.
The BBC has spoken to a Hamas figure who claims the militant group is willing to call thousands of fighters into the city, raising fears of intense fighting where many civilians remain.
Izz al-Din al-Haddad, the group's military commander, has ordered all available fighters across the Strip to converge on the city, preparing for a final, decisive battle.
The Israel Defense Forces (IDF) estimated last week that up to 3,000 Hamas fighters were in the city. The Hamas figure suggested they had 5,000 fighters and threatened suicide attacks, although that tactic has not been widely used in this conflict. Independent verification of these numbers is challenging due to restrictions on press access.
Reports indicate that Israel is utilizing advanced tactics, including rapid thrusts into urban areas and the use of drones to warn civilians of impending attacks.
As the situation escalates, the United Nations estimates that at least 321,000 people have fled south since mid-August, facing significant financial burdens and losing belongings due to the hurried escape.
The humanitarian crisis deepens as remaining residents in Gaza City encounter continuous bombardment, crucial infrastructure damage, and dwindling supplies.
The Israeli military campaign initiated in response to a Hamas-led attack on southern Israel on October 7, 2023, has resulted in staggering casualties, with the Hamas-run health ministry reporting over 65,000 deaths in Gaza.