GEOFF BENNETT: The Israeli military today said it killed the man set to succeed Hezbollah's longtime leader, who was also assassinated by Israel in late September.

The IDF confirmed Hashem Safieddine was killed, along with other top leaders of the militant group, in an early October Beirut airstrike.

Meantime, Hezbollah fired at least 80 rockets on Northern Israel today.

Some were intercepted.

Others left Israelis wounded.

As the war between Israel and Hezbollah expands, its toll on civilians in Lebanon is only worsening.

As Leila Molana-Allen reports, Israeli airstrikes around Beirut have increasingly targeted health care facilities and health care workers.

LEILA MOLANA-ALLEN: An 11-story apartment block leveled in less than a second, dozens of homes and lives demolished.

This missile strike came with a warning, so residents grabbed what they could and fled.

Each night, the streets of Beirut fill with panic as residents run from their homes under threat, but often there's no warning at all.

And now hospitals, as well as homes, are under attack.

Yesterday, Israel's authorities said they believed a Hezbollah cash trove sat under Beirut's Al Sahel Hospital, but said they wouldn't strike it.

Instead, they hit a different one.

Just before midnight, an airstrike was launched at the entrance of Beirut's Rafik Hariri Hospital, flattening four buildings in front of it.

This is the capital's main specialist public hospital, where children injured in the bombing are receiving surgery.

Rescuers dug for hours through the mangled carcass of concrete and iron, searching for survivors.

By morning, 18 were dead and 60 injured.

MOHAMMAD IBRAHIM, Beirut Resident (through translator): I have a brother who's still under the rubble.

His mobile phone is ringing.

We're trying to search for him, but there is no way for a machine to get here.

No one can help us pull him out.

I don't know if he's dead or still alive.

LEILA MOLANA-ALLEN: It's not the first time health care has come under attack in this increasingly brutal war.

More than 100 medics have been killed while working in the past month.

At least 50 health facilities have been targeted.

In spite of the risks, Lebanon's medics and rescue workers, who are all volunteers, in donation-funded ambulances, continue to respond to distress calls.

Ali and his team are based in Saida, one of the south's main coastal cities, and inside the zone Israel says it will target.

He and his team have worked nonstop for weeks.

Hours before we joined Ali's crew, five of his friends were killed when the church they were sleeping in while running rescue operations was bombed.

ALI DAHER, Saida Civil Defense Volunteer (through translator): It's heartbreaking what happened yesterday.

We have repeatedly appealed to international organizations that targeting ambulances and paramedics is internationally unlawful, but no one has helped.

LEILA MOLANA-ALLEN: These volunteers have full-time jobs too, but they have put everything on hold to respond to the crisis.

MAMDOUH AL KURDI, Saida Civil Defense Volunteer (through translator): Even if there's danger, we rush to help.

Our only goal is to save a life and assist someone in need.

Yes, there's risk, but, honestly, sometimes, we don't even think about the danger when we see an injured child or anyone else in distress.

LEILA MOLANA-ALLEN: When Mamdouh and his team responded to a strike on an apartment complex in a town nearby, he couldn't believe what he was seeing.

MAMDOUH AL KURDI (through translator): The scene was terrifying and utterly heartbreaking.

There were children, just pieces of children.

I will never forget one child.

I was able to recover the head and arm, but the rest of the body was never found, just small fragments less than an inch in size.

We were picking up the pieces.

It was a massacre in every sense of the word.

LEILA MOLANA-ALLEN: Mamdouh says the sheer scale of the destruction was overwhelming.

They worked for 72 hours pulling bodies from the rubble.

MAMDOUH AL KURDI (through translator): We try to hold ourselves together as much as possible, but it's tough.

One experience really stayed with me.

While we were clearing the rubble and retrieving the dead, we found an older man and a woman wrapped together, trying to protect each other, both dead, both scared, together in their final moments beneath the rubble.

LEILA MOLANA-ALLEN: Mamdouh knows what he's risking.

MAMDOUH AL KURDI (through translator): We receive many threats and are constantly exposed to airstrikes.

They don't differentiate at all between military personnel, civilians or paramedics.

Anyone trying to do their duty is at risk.

LEILA MOLANA-ALLEN: Ghassan Suheim, who runs the civil defense unit in Beirut's Dahiyeh suburbs, has lost 18 of his volunteers in a month.

Ghassan (ph) was the first to die four weeks ago.

He wasn't just a colleague, but a friend.

GHASSAN SUHEIM, Dahiyeh Civil Defense Unit (through translator): He rescued two children who were still alive.

The rubble fell on him as the building was collapsing, and he got injured, but he never took time to rest.

He insisted on staying.

He worked through the whole night.

I left him at 8:00 a.m. At 8:30, they called me from the site telling me he had suffocated.

LEILA MOLANA-ALLEN: Ghassan died under the rubble, having saved dozens of lives.

Ghassan says each member of his team would do the same.

GHASSAN SUHEIM (through translator): It's normal to be afraid.

We wouldn't be human if we weren't.

But determination, strength and believing in this humanitarian work makes us fearless.

We won't abandon our people, no matter how intense the bombings and destruction gets.

LEILA MOLANA-ALLEN: Attacking medical workers and striking health care facilities are war crimes.

But as the red lines of international law have blurred in this conflict, so too has accountability from the international community.

The U.N. and NGOs are crying out for tighter restrictions to stall the use of U.S.-supplied weapons on civilian infrastructure.

Few here believe Israel's American allies will take action.

For the "PBS News Hour," I'm Leila Molana-Allen in Saida, Lebanon.