In December 1984, a cloud of poison gas escaped from the Union Carbide factory in Bhopal and went on to kill thousands of people. Twenty-five years later, the tragedy continues to dominate the lives of those who live in the city, as Allan Little discovered.
Half a million people were exposed to the poison gas in 1984
Swaraj Puri - urbane, eloquent, hospitable - tugs up a sleeve to reveal a series of little white scars on the inside of his left wrist.
"I can't remember," he says, "how often they had to puncture the vein to measure the cyanide in my blood. It is amazing I'm still alive I suppose."
Mr Puri was the police chief in the state of Madhya Pradesh that night. Roused from his bed after midnight, he made straight for the plant to find out what was going on with still no notion of the scale of the catastrophe that was being unleashed.
"In the control room there was only one official," he told me, "a very junior sort of a person. I asked him what had leaked and from where. He said he didn't know. Did he have any way to find out, I asked. He said no."
Mr Puri climbed to the highest part of the plant that night.
"It is probably what saved me," he said.
"The poisonous gas methyl isocyanate is heavier than air so, when it escaped from the plant, it settled in a dense cloud and moved silently through the poor neighbourhoods around the plant.
"I could see," he said, "the black density of the poisonous cloud making its slow progress through the dimly lit streets."
Twenty-five years on, Mrs Hazira Bee remembers the bodies lying in the streets, the suddenness of it, people leaping from their beds and dying in their nightclothes.
"There was a dairy over there," she says. "All the buffaloes were dead. We ran in terror."
Imagine the terrible randomness, the whim of it because the direction of the wind determined whether you lived or died.
Hazira Bee is indefatigable in her thirst for redress.
She petitions, she marches and she clambers on to the cheap compartments of the night train to Delhi to lead a demonstration at the headquarters of Dow Chemical, the company that bought Union Carbide.
Hazira Bee is still waiting, she says, for justice.
In 1989, the Indian government reached an out-of-court settlement with Union Carbide.
The company paid $470m (£285.4m) in compensation. This represented the insurance value plus interest.
The Indian government had initially demanded almost 10 times that amount.
The money agreed was enough to build a hospital for those who survived but would never work again.
Half a million people were exposed to the gas - each would get about a $1,000 (£607) in compensation.
The deal also represented a full and final settlement of Union Carbide's liabilities.
For Dow Chemical the matter is now closed. It is not, however, a closed matter for the people of the affected areas.
Night of the gas
There is a small, very special group of people who are vital to our trade of reporting the difficult places of the world. They are known to us as local fixers and without them we reporters would not be able to do our jobs.
No-one has ever been successfully prosecuted for what happened at Bhopal
Our local fixer in Bhopal is called Sanjay. This is his story.
He was five months old on the night of the gas, the youngest of eight brothers and sisters.
"My 11-year-old sister picked me up and wrapped me in a blanket and ran from the gas," he said.
The family had gone to bed that night as usual. When the sun came up the next morning, Sanjay's mother, his father and five of his seven siblings were dead. Sanjay would grow up in an orphanage.
Sanjay's sole surviving brother, Sunil, was 13 that night. Later, as an adult, Sunil joined a charitable organisation called Sambhavna as a full-time organiser and campaigner, travelling in Europe and the United States as well as in India to raise awareness and funds.
With the compensation they eventually received, he and Sanjay bought an apartment and Sanjay moved out of the orphanage and back to what was left of his family.
But Sunil never fully recovered from the night of the gas. Three years ago, when Sanjay was away in Delhi, Sunil was alone in their shared flat and committed suicide at the age of 35.
Sanjay is a bright, funny, charming man with an irrepressible joie de vivre. But the world's worst industrial disaster has shaped him. Bereavement has walked with him through his life.
Mr Puri, the police chief, arrested Union Carbide's American chairman Warren Anderson a few days after the disaster.
Mr Anderson was released on bail and allowed to fly home to the United States, where he lives in retirement.
No-one has ever been successfully prosecuted for what happened at Bhopal.
"There is a tremendous frustration among the people that there has been no justice," says Mr Puri.
"I feel it too. On December 3rd each year, I go quietly to the place where we buried a lot of the children, just to remember", he says, "and to pray."
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