TEL AVIV, Israel — 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.

CAIRO, Oct 12 (Reuters) - Israeli military strikes on Gaza overnight killed at least 19 Palestinians, medics said on Saturday, while forces continued to push deeper into the Jabalia area, where international relief agencies say thousands of people are trapped.

The Israeli military is carrying out a widespread operation in northern Gaza, issuing evacuation orders and blocking food supplies, just weeks after Prime Minister Benjamin Netanyahu was reported to be mulling a plan to besiege the area to starve Hamas and force it to release hostages.