AMNA NAWAZ: The conflict between Israel and Hezbollah began the day after the Hamas October attacks last year, with the militants striking Israel's north with rockets and artillery.

GEOFF BENNETT: We have reported on the toll on Northern Israel and lives lost and lives disrupted by evacuations and displacement due to the violent clashes.

Now special correspondent Simona Foltyn takes us to the Lebanese side of the border.

SIMONA FOLTYN: A race against time as fighting and flames engulf Southern Lebanon.

We are with the Lebanese Civil Defense in Khiyam, one of the hot spots of a widening war between Hezbollah and Israel.

Since fighting began in October, there's been a sharp increase in fires here.

During all of last year, this team responded to a total of 55 fires.

Now it's more than 20 per month.

The vast majority have been caused by Israeli bombardment, and as Salem Zarush and his colleagues deploy, there's no guarantee that the shelling has stopped.

SALEM ZARUSH, Lebanese Civil Defense (through translator): We're afraid because we're going to a dangerous area, an area under bombardment.

Of course there's fear.

Maybe we will come back.

Maybe we won't.

SIMONA FOLTYN: They have to work fast and get out of what is an active war zone.

We are about two miles from the closest Israeli position, well within reach of Israeli tanks.

The planes around Khiyam have been pounded with Israeli strikes every single day.

And the civil defense is the first one to respond on site.

But they have very little equipment to contain the fire, no protective clothing to shield them from flames, no bulletproof vests to dampen the impact of incoming fire.

The Civil Defense is Lebanon's public emergency service, but their chief admits resources are scarce.

Lebanon's state collapsed long before this conflict flared.

ANIS ALBA, Lebanese Civil Defense (through translator): Of course, we need a lot of things.

Our cars break down a lot.

They're more than 20 years old.

We lack personal protective gear like body armor, vests and helmets.

We are working with our bare flesh.

SIMONA FOLTYN: The broken wind shield a reminder that first responders have not been spared.

The IDF has killed more than 20 paramedics since the conflict began, according to a U.N. tally.

Despite the risk, they persevere.

SALEM ZARUSH (through translator): We have to answer the call and protect the people's livelihoods.

The people trust us.

They're expecting us to respond.

SIMONA FOLTYN: Salem has a wife and two small children.

SALEM ZARUSH (through translator): Our mission has become more important than our children.

Our families have stayed and they endure the pressure alongside us.

SIMONA FOLTYN: They spot another fire further uphill.

We drive towards it, passing residential buildings damaged in recent fighting.

Most of Khiyam's residents have fled, leaving their homes, their beloved olive groves and pomegranate trees at the mercy of the bombs.

The few civilians left are Syrian refugees who have nowhere to go.

Once again trapped by conflict, all they can do is help the understaffed Civil Defense.

SALEM ZARUSH (through translator): We have become few.

The volunteers who used to help us have left with their families, so we are forced to deploy in small numbers.

SIMONA FOLTYN: Soon after we leave, the shelling of Khiyam resumes.

Along with allied Palestinian and Lebanese armed groups, Hezbollah uses these areas as a launching pad for attacks on Israel.

But Israeli strikes on Lebanon are far more numerous, and in addition to taking out fighters, they have killed dozens of civilians and destroyed civilian infrastructure.

That day, this pharmacy was hit.

Hussain Idriss fled Khiyam months ago with an airstrike leveled a nearby house.

The shockwave ripped through his apartment.

So this is your balcony?

HUSSAIN IDRISS, Displaced From Khiyam (through translator): All the glass broke.

I quickly packed my stuff, got into the car and drove off to Beirut.

SIMONA FOLTYN: He has since rented this apartment in a neighboring village.

HUSSAIN IDRISS (through translator): In my opinion, Israel targets the civilian infrastructure so that people vacate these areas.

Of course, a pharmacy isn't a military post.

The same way Israel has empty areas, they want us to have empty areas.

The same way they have been displaced, they want us to be displaced.

SIMONA FOLTYN: This tit for tat has created a no-go zone for civilians.

The only safe way to get there is with U.N. peacekeepers, known here as UNIFIL.

We are headed for the U.N. blue line separating Lebanon and Israel.

As we approach, the gunner ducks inside and closes the lid.

From now on, we're not allowed to leave the armored vehicles.

LT. COL. JOSE IRISARRI, UNIFIL: We are not the target, but maybe one attack could fall close to the patrol.

SIMONA FOLTYN: Lieutenant Colonel Jose Irisarri is part of a Spanish battalion.

Do you think that your presence and these patrols have any impact in terms of calming the situation?

LT. COL. JOSE IRISARRI: It's the only way to avoid an open war in the south.

UNIFIL wasn't here, the level of attacks and the kind of attacks would be much worse.

SIMONA FOLTYN: The destruction tells us we're getting closer to the blue line.

On the other side of this wall lies Israel.

The Lebanese village of Kfarkela has become a ghost town.

We haven't seen a single civilian except for a few paramedics.

The village is entirely deserted, and this is not just Kfarkela.

This is what the entire border areas look like.

A quick stop at a U.N. post not far from the triangle where Lebanon, Israel and Syria meet.

The official borders have yet to be demarcated.

Much of this land remains disputed, a matter that further complicates a resolution to this long-lasting conflict.

LT. COL. JOSE IRISARRI: There are so many factors.

They have to get in agreement with so many people.

SIMONA FOLTYN: The Blue Helmets have been here since Israel first invaded Lebanon in 1978 and are supposed to help the Lebanese Armed Forces, or LAF, keep these areas free of Hezbollah.

But UNIFIL has no mandate to use force.

These bullets are only for self-defense.

Throughout the patrol, we see very little of the Lebanese army.

The international community and also the Israeli government are pushing for the Lebanese army to take over security in this area, but we don't see them with you.

LT. COL. JOSE IRISARRI: Twenty percent of our patrols are with the LAF soldiers.

SIMONA FOLTYN: Which is not much.

LT. COL. JOSE IRISARRI: But it's what -- nowadays, we are -- no, it's not mess.

We are pushing to the patrols of the Lebanese army to participate as much as possible with us.

SIMONA FOLTYN: The ground truth is that Hezbollah, formed in the 1980s to fight the Israeli occupation of Lebanon, has become more powerful than the army.

This latest conflict is bolstering its already strong position and once again turning Lebanon's south into a battleground.

For the "PBS News Hour," I'm Simona Foltyn on Lebanon's border with Israel.