By Duncan Kennedy
BBC News, Mexico
Mexico's dirty war - in which political dissenters "disappeared" - was much less publicised than similiar events in other Latin American countries. But the first attempts are now being made to find some of those who were buried in mass graves in the 1960s and 70s.
Decades on, the first suspected mass grave is now being excavated
I have always found it strange and sad that the most awful things happen in the most beautiful of places.
I remember in Kosovo - during the conflict between the Serbs and ethnic Albanians - being taken down a country track.
The trees on either side leant over in exact, interlocking, symmetry and formed a lush green tunnel ahead of us.
It could have been New England or Provence.
But at the end of this track was a mass grave full of decaying corpses.
It was the same with my trip to Western Mexico.
An hour or so north of Acapulco lies the town of Atoyac.
A pretty, but typically poor Mexican town, where you negotiate the potholes with care.
We had come to find its former army base.
After being pointed in the right direction, we arrived at the gate of the base, the same barrier that once must have instilled terror into those who had been brought here against their will.
Inside was a series of white-walled, single-floor concrete huts. About 10 of them, around a square.
Beyond lay beautiful, mountainous slopes, carpeted with vivid green jungle.
But, as with Kosovo, I knew my stunning vista was only a deceptive prelude to something more horrifying.
Soon, our guide - from one of Mexico's human rights groups - was leading us to the back of the camp.
At the end was a brick wall. We peered over. There, in the garden, among the wild yellow and white flowers, were 20 people with hard hats and sweating foreheads, all digging.
They were prising the earth from the ground, where years before others had shovelled out the same soil, only with more sinister motives.
This was almost certainly a mass grave. And now the men in hard hats were digging for human remains.
According to human rights organisations, this was a death camp in Mexico's dirty war of the 1960s and 70s.
Up to 470 people are thought to have been tortured and killed at this one location, we were told. And there were many other camps.
It had taken years to persuade the government to allow this dig to take place, Mexico's first.
To have the words "Mexico", "dirty war" and "death camp" all appear in the same sentence, might come as a shock to some people.
We all know about Argentina, Chile, El Salvador, Guatemala, but Mexico?
I met the family of Rosendo Radilla, a local man brought here in 1974.
Rosendo Radilla was 10 when his father was arrested
His son, also called Rosendo, was just 10 years old when soldiers came to take away his father.
His eyes swollen with tears, he tells me his father was active in council politics. But he was never the left-wing anarchist he was accused of being, by the commanding officer of the late-night snatch squad.
Rosendo and his 11 brothers and sisters never saw their father again. They now believe him to be one of those buried in this garden.
But Mexico's dirty war was not just conducted behind the walls of secluded army camps.
One of the most infamous incidents occurred during a student demonstration in the centre of the country's capital, Mexico City. It was 2 October 1968 at La Plaza De Las Tres Culturas.
Elements in the government of the ruling right-wing PRI party decided the demonstration was a national threat. So they sent in teams of plain-clothes soldiers, who started firing on the crowd.
There is no clamour here for truth and reconciliation commissions
Conservative estimates now suggest at least 300 people died in the square. Others believe as many as 800 were killed.
Most of the bodies were taken away in secret.
Incredibly, the massacre - for that is what it was - took place just 10 days before the start of the 1968 Olympic games in the city.
The country's press were intimidated into saying practically nothing and the games duly went ahead.
Mexico's security forces were trained by the Americans, just as others in Latin American states were at the time.
Up to 2,000 people are known to have disappeared in the dirty war
Back at the old army camp in Atoyac, the digging continues. It will go on for some time.
There is no clamour here for truth and reconciliation commissions, as in other places.
It all happened a long time ago. The evidence pointing to the perpetrators is now as flimsy as the forensic fragments now being placed in plastic bags.
There are documented cases of up to 2,000 people who are known to have disappeared during this period.
But their families will probably never find out exactly what happened to them, no matter how long they spend in this beautiful, but blighted, place.
From Our Own Correspondent was broadcast on Saturday, 19 July, 2008 at 1130 BST on BBC Radio 4. Please check the programme schedules for World Service transmission times.