(NewsNation) — The Israeli Defense Forces say they are taking the battle underground in order to dismantle Hamas’ tunnel system as fighting in Gaza intensifies.

The IDF is now focusing on knocking out the tunnels as well as the weapons stockpiled by Hamas in Gaza. They have found stockpiles of rockets, missiles and explosive devices in the tunnels, as seen in videos provided by the IDF.

Northern Gaza has seen intense fighting over the past day, with the Israeli Defense Ministry saying it believes Hamas is at a breaking point. The southern region, though, may see weeks more of fighting based on Israeli reports.

Israel says about 500 Hamas fighters have surrendered within the past month, and the Defense Ministry is calling on the rest of Hamas and anyone else opposing Israel in Gaza to do the same.

“I call from here to all those battalions to the terrorists to their commanders and to the battalion commanders surrender. If you surrender, you can save your lives. If not, your fate is sealed. To the terrorist at the opening of the tunnel, there is no alternative. He can choose one of two: to unconditionally surrender or die,” said Israeli Defense Minister Yoav Gallant.

On Tuesday, the IDF reported two hostage bodies were recovered: 28-year-old Eden Zecharya, who was taken hostage at the Supernova music festival on Oct. 7, and 36-year-old soldier Ziv Dado.

President Joe Biden plans to meet with the families of American hostages Wednesday. It is estimated seven American men and one American woman are still unaccounted for.