AMNA NAWAZ: Indonesia is battling its worst wildfires in more than a decade, made worse by El Nino weather patterns.

Many of these fires were deliberately set to clear land for farming, including palm oil plantations.

Rain this week brought some relief, but the rainy season isn't expected until next month.

More than 12,000 schools across Indonesia have closed because of the toxic haze, which has also spread to neighboring countries.

In Central Kalimantan, where children have been out of class for weeks, one school principal and photographer has been documenting the fires on social media.

He spoke to us from an empty classroom at the Golden Christian Middle School.

NATANAEL UNDAS, Photographer: My name is Natanael Undas.

I'm a school principal Palangkaraya, Central Kalimantan.

It is a kind of rain forest and then a lot of native trees.

We got a lot of fruits.

We got a lot of tree for timber.

But now the sky, it turns yellow.

It turns like hell.

The last time I saw the blue sky was in August '20.

The haze come to our city.

And then the fire goes closer, closer, closer and closer.

And then, like the last week, it was a really huge fire in the city.

I'm really sad, because my student lost a lot of school hour and learning experience.

If you go outside in a school hour, probably at 8:00, 9:00 a.m.

in the morning, they go outside, they play with other friends without a mask and thinking it's just like a school holiday in the middle of yellow sky.

This fire is not natural disaster at all.

It is manmade disaster.

We're hoping the rain will come soon.

Last night, there was a huge rain, even only for 17 to 25 minutes.

We're longing to inhale the smell of rain, the smell of air, the smell of wet leaves, the smell of wet land.

Last night, when it was raining, I open a little bit of my door, and I try to smell the rain.

It's like a smelling the perfume that's mixed with smoke.

It's still poisoned, so I need to close it.

Not many people knows about what really happening right now, what we are experiencing, especially what we are inhaling.

A lot of children are suffering because of respiratory issue.

I don't want my daughter having the same experience.

I don't want to lose this generation.

We still can save this.