GEOFF BENNETT: Welcome to the "NewsHour."

With tens of thousands of civilians still fleeing the heavy fighting in Northern Gaza, Israel agreed today to open a second route south and pause fighting for a few hours each day.

AMNA NAWAZ: Late today, President Biden says Israel has a -- quote -- "obligation" to distinguish between terrorists and civilians and follow international law.

Leila Molana-Allen reports.

LEILA MOLANA-ALLEN: As Israeli ground forces push deeper into Gaza, a rare look inside the northern strip showed abandoned neighborhoods scarred by battle.

It also gave clues about how Hamas operates.

The IDF claims they found these weapons in a workshop under an apartment building.

MAN (through translator): You can see a pink dresser and a little girl's bed in a residential home.

LEILA MOLANA-ALLEN: A few floors above, this bedroom appears to have belonged to young girls.

Israel says it's evidence that Hamas hides within and behind the civilian population.

YOAV GALLANT, Israeli Defense Minister (through translator): This entire city is one big terror base.

There are miles of tunnels underground.

They connect to hospitals, to schools.

LEILA MOLANA-ALLEN: Now the IDF is closing in on Gaza City's Al Shifa Hospital.

It claims Hamas' main command center is located underneath, which Hamas and hospital staff deny.

DR. MUHAMMAD ZAQOUT, Director General, Gaza Hospitals: See, we have many patients placed here.

LEILA MOLANA-ALLEN: Inside Al Shifa are Gaza's most vulnerable.

The director general of Gaza's hospitals, Dr. Mohammed Zaqout, sent the "NewsHour" this video earlier this week.

DR. MUHAMMAD ZAQOUT: It's overwhelmed with the huge number of patients here.

LEILA MOLANA-ALLEN: It's overflowing with people injured by Israeli airstrikes, and thousands of civilians taking shelter in what they hope is a safe zone.

Tens of thousands of Palestinians have already fled the northern part of strip via a humanitarian corridor along Gaza's main highway.

The White House announced today that Israel agreed to another corridor along Gaza's coast, where there will be daily four-hour humanitarian pauses in the bombing.

Also today, it's been reported that mediators are trying to negotiate a three-day pause in fighting in exchange for a dozen hostages held by Hamas.

President Biden confirmed this morning that he asked Israeli Prime Minister Benjamin Netanyahu for the swap, but gave no details.

QUESTION: Did you ask him to pause for three days to get the hostages out?

JOE BIDEN, President of the United States: Yes.

I have asked for even a longer pause for some of them.

LEILA MOLANA-ALLEN: And Hamas announced today it's ready to release an elderly woman and a young boy for humanitarian reasons, but said no deal had been made yet with Israel.

In France, world leaders gathered today for a Gaza aid conference.

EMMANUEL MACRON, French President (through translator): And we worry about the humanitarian situation in Gaza.

LEILA MOLANA-ALLEN: The host, French President Emmanuel Macron, appealed to Israel to protect the innocent.

EMMANUEL MACRON (through translator): Civilians must be protected.

And this is absolutely vital.

It's not negotiable.

Its also a condition for the effectiveness of our fight against violence.

LEILA MOLANA-ALLEN: Others were more direct, like Prime Minister of the Palestinian Authority Mohammad Shtayyeh.

MOHAMMAD SHTAYYEH, Palestinian Prime Minister (through translator): How many Palestinians must be killed for the war to stop?

What Israel is doing is not waging war against Hamas, but against the whole Palestinian people.

LEILA MOLANA-ALLEN: The people of Gaza need help more than ever.

On top of Israel's constant aerial bombardment, the World Health Organization warns, disease is spreading rapidly.

Some, like the Kullab family, have chosen to move back to their bombed homes after staying in shelters.

JIHAN KULLAB, Gaza Strip Resident (through translator): My home is completely destroyed.

Look at the damage we live in.

I couldn't stand living surrounded by people, diseases, in hospitals, on the streets, so I came back to my home here.

LEILA MOLANA-ALLEN: Like most other families in Gaza now, they live without electricity or running water and with barely any food.

While some aid is entering the strip each day, the U.N. says it's just a drop in the ocean of need.

For the "PBS NewsHour," I'm Leila Molana-Allen in Tel Aviv.