A Hezbollah drone attack on an army base in central Israel killed four soldiers and severely wounded seven others Sunday, the military said, in the deadliest strike by the militant group since Israel launched its ground invasion of Lebanon nearly two weeks ago.

Israeli forces expanded their ground operations into northern Gaza, reaching the northern edge of Gaza City and bombarding parts of the Sheikh Radwan neighborhood, according to local residents. Tanks and artillery fire forced many families to flee as Israeli troops isolated the towns of Beit Hanoun,

The humanitarian crisis in the northern Gaza Strip deepened Saturday as an Israeli bombardment killed at least 20 people, trapped thousands more and prompted one of the area’s last functioning hospitals to issue desperate pleas for assistance.