By the time they had finished kicking him, Nahaman Carmona Lopez, 13, had bruising over 70 per cent of his body. He had six broken ribs and a ruptured liver. Left on the street by his assailants, four uniformed Guatemala City policemen, Nahaman died a few days later.
"He was in the wrong place at the wrong time, hanging out on the streets where he lived," says Pedro Gunson, Scottish co-ordinator of Casa Alianza, an international charity dedicated to the rehabilitation and defence of street children.
"The authorities `clean' the streets. They're not interested in protecting, caring for or rehabilitating the children. Deaths like Nahaman's are often blamed on gang warfare and, while such deaths do occur, this is often just used as an excuse by the guilty authorities," he says.
But Nahaman's death in 1990 was to prove a landmark case. The executive director of Casa Alianza in Guatemala went to the police station to file a complaint against the officers and to start legal proceedings.
Within days he was subjected to death threats. Wreaths were delivered to his wife and family, and the Casa Alianza office was sprayed with machine- gun fire. But the charity stuck to its guns and after two years it got a conviction - only the second time in Guatemalan legal history that such a conviction was achieved.
But the victory was to prove a pyrrhic one. In January 2009, CA had to pull out of Guatemala because of continuing difficulties carrying out its work, though it intends to re-establish itself in the country this autumn, after much preliminary work with community groups.
"As an NGO (non-governmental organisation), we try to work in partnership with governments to tackle the issue of street children and violence against them," says Mr Gunson.
"However, we often face huge challenges - namely, that they want our services, our programmes of aid and educational support for street children, but they don't like the international attention we can bring."
Casa Alianza received the Swedish Olof Palme Prize for its "courageous defence" of street children in 1996; the International Award for Children's Rights in 1999; and the Conrad N. Hilton Humanitarian Award in 2000.
"We work in Honduras, Mexico and Nicaragua, but our relationship with these governments is not always smooth because we shed light in dark corners."
Particularly dark corners in recent months have been the streets of Tegucigalpa and San Pedro Sula in Honduras. After a military coup last year, a midday curfew was called.
"Where are children supposed to go when there's a daytime, never mind a night-time curfew? There is nowhere to go," says Mr Gunson.
The result was that children were arrested, beaten, raped and even tortured. According to CA records, in the period after the coup in June 2009 and the elections at the end of November, 388 street children were murdered.
Why would anyone torture a child? "If you want a human - or a humanitarian - answer, I can't give you one. They might be suspected of being members of criminal gangs. But, again, it's not all government; there are vigilantes, extremist groups and individuals who do these things," says Mr Gunson.
"These things may happen to a young person who is trying to break a cycle of sexual exploitation. But the point is the government and the new president are not protecting the rights of children in Honduras."
CA's latest figures show that the number of children and young people (under-23s) killed on the streets of Honduras in April this year was 85, bringing the total number of killings recorded by CA Honduras since 1998 to 5,380.
In its present campaign to bring the Honduran government to account, CA works with local legislators and courts to seek juvenile justice as well as urging individuals across the world to write letters to governments and embassies and, in Scotland, to send appeals to MSPs, MPs and MEPs.
In his role as the first Scottish co-ordinator of Casa Alianza, Mr Gunson regularly talks to schools, pupils, church groups and other charity organisations to raise awareness and garner funds. He took up his voluntary post nine months ago and one of his first objectives is to gain separate charitable status in Scotland (CA is a registered UK Charity) in order to work more easily and efficiently with the Scottish Government, Parliament, local authorities and other NGOs, charities and organisations.
"With its Enlightenment tradition, Scotland has a strong sense of social justice and we seek that support. We only have two part-time paid members in the UK charity and that is how we intend to keep things, because we want the money to go where it's needed," he says.
Mr Gunson is a supply teacher for special educational needs in Edinburgh. In 1992, while still at school in Australia, he chose to study in Honduras for a year because he "wanted something life-changing". It was there, while living with a family and attending a state school (50 pupils per class), that he got to know "a warm and beautiful people" and found his vocation for teaching and social justice.
Defending children's rights is only part of the charity's work. A lot of the money raised helps to support an outreach service (including emergency first aid and food), arts and recreation programmes for 8,000 street children every year, and the charity's residential homes for 2,000 young people.
In spite of fighting against tremendous odds, Casa Alianza is a success story. "Our main goal is to get children back to families - where that is both safe and possible - and to get them back into school. We work with families over two years on average after family reintegration, in order to rehabilitate the child securely, and we have an 85 per cent success rate of children not returning to the street," says Mr Gunson.
The reasons why so many children end up on the street in the first place are many and complex, ranging from family breakdown, violence and abuse, as well as parental alcohol and drug abuse, to the sheer number of children living in poverty-stricken homes where extra mouths simply cannot be fed.
"In Honduras, for example, 15 families hold nearly all the wealth, land and power. There is no middle class and no health or welfare system. There is only a massive, massive gap between the rich and the poor," says Mr Gunson.
Once children are on the street, they are prey to gang culture and drugs, usually solvents and glues that are easily obtainable and numb the cold and pain of feral life.
Sexual exploitation is also common for boys and girls. Trafficking is increasing within the countries where CA operates and beyond to the USA and Europe. Mr Gunson says: "100,000 children are trafficked around the world annually. It is now a US $20 billion trade."
In countries where CA operates, street children are turned away from hospitals, even in emergency cases, because they don't have the necessary paperwork andor money.
"They don't officially exist and you can't get the paperwork often, because one or other parent is missing, not known or dead. If you don't have paperwork or money andor the right contact, you're invisible.
"Our work is literally a matter of life or death. If we weren't in these countries, the children we help and protect would most likely die of curable diseases (such as cholera and malaria), drug abuse or starvation - or enter the downward spiral of gang culture, or be killed."
The situation facing these street children is perfectly - and tragically - encapsulated by the epitaph on murdered 13-year-old Nahaman's gravestone: "I only wanted to be a child, but they wouldn't let me."
Poem by Ludvin Omar Valdes, 17, former resident of Casa Alianza, Guatemala, murdered in 1998:
To you hidden youngster
Who has been left forgotten?
Who the rich have feared
For being a beggar
Because they have not suffered
What it means not to have a shelter
You that has everything, tell me
Why must this way of living
Be so forbidden
For my people that I love so
To you, my dear friend, I say
Don't let yourself be forgotten
You that has had no father
And therefore has slept
On the streets
Making a doorway your only nest
That the rich have invaded
To be able to finish you off
SUCCESS STORY - Manuel, Mexico City
At age 15, Manuel left home (a camper van he shared with his parents and two brothers) because of violence.
"All of my family would fight and there were lots of arguments. I didn't like it that they would fight with each other, so I left.
"I was visiting nieces and nephews when Casa Alianza counsellors found me. They said they would support me, help me with my studies, help me to find work, so I said `yes' and I went with them.
"They helped me in communicating with people. I was scared of everyone. They would ask me, `Why are you so isolated?' and I would say, `Because I'm scared'.
"They helped me in communicating with others, in appreciating myself for who I am, telling me that I don't have to tell myself that I can't do this or that and they helped me in getting all the problems I had off my chest.
"A normal day would be doing chores like cleaning up, going to school, doing homework and some recreation time. I liked the parties that they would hold, like the celebration for the Day of the Dead.
"I'm now 20 years old and work in a glass factory, a job I got through Casa Alianza, and a job I love.
"I now live at home with my mother and I see my father once a week. My brothers have left home and have lives of their own.
"My family changed because of me. There is no violence any more. They have seen I went to school and found a good and stable job. So it was because of me that they changed.
"Casa Alianza is a real support, enabling me to move forward in my life. If I hadn't come here and no one had believed in me, then I probably would be on the streets taking drugs."