By Philippa Fogarty
BBC News, Pailin
Supervisors clear the area before detonating any landmines they find
On a wooded hillside above a village in north-west Cambodia, a man speaks into a radio.
Figures in body armour and visors head downhill to shelter from the sun under some trees.
A whistle sounds and then a siren. A few minutes later a loud crack echoes around the countryside. Grey smoke floats into the air.
The first landmine of the morning has been destroyed.
It was a Chinese-made type 72A - a small, green object that blows off the leg that treads on it or the arm that picks it up.
The team head back up the hill. There are many more mines to go.
This is a scene that is repeated day after day across Cambodia, one of the most heavily mined countries in the world.
Between four and six million landmines are thought to have been laid during the country's three decades of civil war.
Several million landmines planted over 30 years of civil conflict
Highest concentration of landmines in north-western areas along the Thai border
Many eastern areas contaminated by unexploded ordnance
Khmer Rouge fighters, Vietnamese troops and government forces all planted devices, but did not record where or how many. Huge areas of land were contaminated, particularly in western border regions where the fighting was fiercest.
Across the country, victims of landmine blasts are a strikingly visible presence. More than 40,000 people are thought to have lost limbs.
Work to remove the mines has been going on ever since the conflict ended, and a great deal of progress has been made. But there is a lot still to do.
"Cambodia still has a significant landmine problem," says Rupert Leighton, Cambodia country director of the Mines Advisory Group. "They are not starting to dry up yet."
Casualties have fallen significantly in recent years, from more than 2,000 annually in the early 1990s to less than a quarter of that in 2006.
This is because the movement of displaced people has subsided, people know more about landmines and more clearance has been carried out. There are also fewer people facing acute hunger, meaning fewer people foraging in the forests.
The key issue now, says Mr Leighton, is the fact that so much land still cannot be used - at a time when competition for it has become fierce.
Boeung Prolite lies 6 km ( 4 miles) from the Thai border, not far from the former Khmer Rouge stronghold of Pailin.
For more than two decades a guerrilla conflict raged in this area - and both sides laid mines extensively.
A red triangle marks a landmine which must be blown up
People began settling in Boeung Prolite in the 1990s, when the fighting wound down.
About 30% of villagers are former Khmer Rouge fighters, the rest are new arrivals from other provinces. They live in simple wooden houses and grow crops for subsistence and sale.
On high ground above the village lies a mine field about the size of 19 football pitches.
This one was laid mainly by the Khmer Rouge and, as well as 72As, contains type 69s - small grey mines which spring upwards to explode at waist height.
Nine casualties have been recorded on this minefield over the years. The last was in 2002, a farmer who wanted to plant more crops.
Roeu Sokhom heads the team that is clearing the site. He, a deputy supervisor, a medic, a driver and 12 deminers began work there in early March after the initial site survey was complete.
Using metal detectors to examine every inch of ground, working in high heat and humidity, they have already destroyed dozens of mines. They expect to complete the job by the end of June.
When it is done, 10 local families, comprising a total of 59 people, will be able to farm there, Roeu Sokhom says.
Some have already moved in to plant up earth cleared only days before, such is their hunger for land.
One of the mine clearers is 26 year-old Khoeun Sokhorn. She lives with her family in a village near Pailin and has been a deminer for two years.
Khoeun Sokhorn demonstrates how she checks the earth for landmines
In 2002, she went into the forest to gather firewood. The area had been classified as "suspect", but people had been going there for years and everyone thought it was safe. A landmine blew off her right leg.
She wants to clear mines so that no-one else gets hurt the way she did, she says. She is proud that the number of casualties is continuing to fall.
But when she finds a mine, there is no flash of triumph - she just reports it to her supervisor and moves on to the next one.
She says she will clear mines as long as there is work for her. She does not need to look for another job yet.
"We will never clear all the mines out of Cambodia, but in 10 years we have a reasonable chance of saying that the worst areas have been cleared," says Mr Leighton.
"It depends on funding and also on how we define the finish line - are we talking about impact-free or casualty-free?"
"We could go on working in Cambodia forever, but the law of diminishing returns would mean that we become more and more expensive."
In Khoeun Sokhorn's village there are several mine fields that need to be cleared.
She is married and she has a three-year-old daughter.
The little girl does not know what a landmine is yet. But, Khoeun Sokhorn says, she is old enough to know that she must not go into certain parts of the forest.