The BBC's Jonathan Head reports on the anti-drug campaign in Thailand that has killed more than 600 people in three weeks.
The Thai government wants to be rid of drug dealing
Just after dawn, a team of police and soldiers burst into a house on the outskirts of Chiang Dao in northern Thailand.
They were heavily armed and led by a sniffer dog. It did not take the dogs long to take up the scent - the sickly-sweet smell of Ya Ba, the mad drug, or methamphetamines.
Five thousand of the pink pills tightly wrapped in plastic were hidden in bushes and an old tree trunk in the garden.
An elderly man was arrested and handcuffed. His tearful son, Song Narong, admitted that his father was one of the estimated one to two million Ya Ba addicts and small-time dealers in Thailand.
"This group of foreign-looking men came around to the house last night trying to make friends to my father and pushing drugs onto him. When I got home last night, my brother told me dad had gone back to using Ya Ba again," Song Narong said.
Others caught up in Thailand's drug war have been making efforts to come off Ya Ba.
Addicts at one rehabilitation centre I visited spent 16 weeks there under close supervision.
Some were sent by the police, others by their families. But statistics show that only 30% will stay off the drug.
One 25-year-old man at the centre, who had been using Ya Ba every day since he was 15, said that he was afraid this could happen to him.
Thai drug users in hospital are at least safe from being shot
"So long as I stay here in the hospital, it is no problem, but I am worried that when I get out and I meet up with friends who have the pills I may start using them again," he said.
He is lucky. Since Prime Minister Thaksin Shinawatra launched his all-out war against narcotics at the beginning of this month, around 600 addicts and dealers have been shot dead in towns and villages across the country.
It has created a climate of fear, so much so that police officers leading drug raids have been finding it difficult to track down suspects.
"They are afraid that we might arrest them, and the penalties are quite severe at this moment... (they are) trying to cut connection...," one officer said.
The authorities have maintained that most of the deaths are at the hands of rival drug dealers.
But the disturbing similarity among the victims - all shot execution style, their bodies found clutching weapons and bags of narcotics, and the fact that there have been no investigations into the killings - has raised suspicions of a deliberate shoot-to-kill policy by the government.
Human rights alarm
Srirak Plipat, director of the Thai branch of Amnesty International, said the human rights group was worried about the way the government was conducting its crackdown on drugs.
"What we are concerned with is the means that the government has been using, and one of them is extra-judicial killings and it has to be that the suspects have to be seen and treated as innocent until they are proved guilty," he said.
"It is not the job of the police or other authorities to do that judgement, it is the court," he said.
At a school in the north-eastern town of Chiang Kham, the childish simplicity of the pictures of pupils enjoying an art lesson betrayed nothing of the horror they witnessed just a few days before.
One of the former pupils, 17-year-old Samritchai Chongham, was gunned down right outside the school gate by an unknown assassin.
The police have not bothered to investigate. His mother, Khampan, insisted her son was not a drug dealer.
"He was a good boy, quiet and hardworking. Why did they have to kill him? Everyone around here agrees. If he was really involved in drugs we would be a rich family, not poor like this," she said.
Drug addiction has reached epidemic proportions in Thailand, but, in its determination to wipe it out, the government has unleashed bloodshed on a scale not seen in this country for more than a decade.