Firefighters are battling the fires that have been raging in the Amazon rainforest for the past three weeks. They have suffered both physical and mental stress, as they march toward massive flames, seeing communities ruined and animals running for their lives. CGTN's correspondent Dan Collyns has more from Bolivia.

Just when it seems like there's nothing left to burn, some of the fires in Bolivia have reignited in places already blackened. The firefighters - mostly made up of trained volunteers - are battling on multiple fronts.

DAN COLLYNS CONCEPCION, BOLIVIA "In this corner of the dry forest there are still hundreds of fires, some of which have become reactivated. That's why the firefighters work at night. Because it's much easier to see the embers and make sure they're fully extinguished. It's hot, and the air is full of ash and smoke and the heat on the ground is so great you can feel it coming through your shoes."

Wielding machetes and shovels and spraying water, they douse the smoking remains.

FIREFIGHTER "We're trying to reduce the fires to a minimum but they are still what we call a category 3 which is still relatively strong, in this area."

In the nearby town of San Ignacio, the firefighters are changing shifts. Army cadets get a medical check-up before they're dispatched to the fire line. Just getting in after eight days of battling fires in the bush, a weary team of volunteer firefighters. They're still overwhelmed by what they experienced.

ANDRES MANACA FIREFIGHTER "Most of all, I'm looking forward to seeing my family - for me personally, it's been a very powerful experience - because the fire nearly trapped me twice, and the first thing I thought of was my family - but thank God, I'm here now!"

Manaca tells how he got his team to safety after a firewhirl reared up as they battled the flames. His colleagues share some of their camera phone images of what they witnessed. All say the saddest part was seeing the destruction of nature as well as animals and birds trying to escape.

Indigenous communities in the forests have suffered.

MARIA DEL CARMEN CARRERAS WORLD WILDLIFE FUND "This situation is very sad because we've been working for a long time with the communities on sustainable forest management which is an important source of their income. At this point, many communities have lost to up to 98% of their forest."

Over the past month, the number of fires has decreased by around two-thirds from a high of more than 10-thousand, but the damage has largely been done. By the most modest estimate, at least one million hectares has burned, environmental groups say the figure is closer to two million. Dan Collyns, in Concepcion, Bolivia.