Israel-Gaza updates: IDF says it expects war to last all of 2024

A quarter of the population is starving because too few trucks enter with food, medicine, fuel and other supplies, according to U.N. monitors.

U.N. monitors said operations at the Israeli-run Kerem Shalom crossing halted for four days this week because of security incidents, such as a drone strike and the seizing of aid by desperate Gaza residents. They said the crossing reopened Friday, and that a total of 81 aid trucks entered Gaza through Kerem Shalom and the Rafah crossing on the Egyptian border -- a fraction of the typical pre-war volume of 500 trucks a day.

The United Nations Agency for Palestine Refugees said Friday that Israeli soldiers fired on a U.N. aid convoy returning from a delivery in northern Gaza, an incident U.N. humanitarian chief Martin Griffiths condemned as "unlawful."

Palestinians reported fierce Israeli tank fire and aerial bombing in Khan Younis in southern Gaza overnight, and strikes appear to be continuing this morning.

Israel said its forces in Gaza eliminated "dozens of terror operatives" in the past day. Planes also carried out a series of air strikes on the Nuseirat camp in central Gaza, according to medics and Palestinian journalists.

Residents in the urban refugee camp of Bureij, a recent hot spot of combat along with Nuseirat, also reported Israeli airstrikes overnight and into Saturday. Israeli forces have been pounding Khan Younis in preparation for an anticipated further advance into the main southern city, swaths of which they captured in early December.

Israel said Saturday its troops have advanced further in southern Gaza, while raiding Hamas sites in Khan Younis, including the headquarters of the terror group’s intelligence division in the city.

According to Israel, the intelligence HQ was responsible for all of Hamas’s intelligence activity in the Khan Younis area.

Israel said that it struck three terror cells in southern Lebanon on Saturday. The IDF also said it carried out strikes against Hezbollah infrastructure and shelled areas in southern Lebanon.

The strikes came amid Hezbollah rocket, missile and drone attacks on northern Israel on Saturday, according to the IDF. According to Israel, 80% of the launches fired by Hezbollah toward Israel fell in Lebanon.

-ABC News' Dana Savir

The IDF said it has located and destroyed a hideout apartment of Yahya Sinwar -- a Hamas leader -- near Gaza City in the northern Gaza Strip.

IDF soldiers examined the apartment using additional technological means and found that a strategic tunnel shaft was located on the basement floor. The soldiers inspected the tunnel shaft and reached a 715-foot tunnel with a depth of over 65 feet that was apparently used by the senior officials of Hamas’ Military and Political Wing, according to the IDF.

The IDF said that the tunnel had an electrical network, ventilation and sewage infrastructure, hideout materials, prayer rooms and resting rooms. The IDF said the tunnel was built so that it would be possible to stay inside it and conduct combat for long periods of time.

-ABC News' Dana Savir