The money changer of Kabul, his daughter and her kidnappers

Murtaza Ahmadi was one of those Afghans who somehow never seemed to suffer from the long war.

No one in his family perished on the front lines with the army or the police, or disappeared for years with the Taliban only to come back in a plywood coffin. No one close to him had the bad luck to be where a bomb went off or to get caught in crossfire, relatives said.

Ahmadi's luck suddenly ran out in March. No bomb or gun was involved, but he was targeted nonetheless — for the bundles of cash he handled in his job every day, and for the 6-year-old daughter more precious to him than any of that.

Earlier in the war, Ahmadi had moved to Kabul, the capital, from his home province of Kapisa, north of the city. He was never a wealthy man, but he found a good job as one of the money changers in the Sarai Shahzada market in Kabul, where men with rubber bands around fat wads of notes hawk their exchange rates in the open air, their loud voices clamouring into unintelligibility.

They buy dollars for 74 or 75 afghanis and sell them for 75 or 76, pocketing the tiny buy/sell spread, out of which they have to pay the rent on their market stalls, often just a glass-topped pushcart stuffed with ragged notes.

On a good day, Ahmadi took home $15, his friends said — enough of an income that he could marry and support a young family in an apartment given to him by his brother.

He and his wife had four children: daughters Satayesh, 8, Mahsa, 6, and Neyayesh, 4, and a son, Mohammad Ibrahim, 2.

"He was very attached to his children, especially Mahsa," said Mohammed Aqa, a fellow money changer. The picture on the screen of his mobile phone was of Mahsa, Aqa said.

After work, Ahmadi liked to take Mahsa out shopping in their neighbourhood, known as the 315 Area, in the north of the city.

On the evening of March 9, a Saturday, the two hit their usual stops. At the bakery near their home, the baker, Esmatullah, sold them a loaf of Uzbek-style round bread. They chose one from the big sloping rack in the curved front display window of the bakery; as usual, Mahsa wanted to carry it, the baker said.

"They always came together," he said. "They were very attached to one another."

They also stopped at the grocery closest to their home, where they were served, as usual, by the grocer's son, Sajad Agha, 18.

But police say Agha and his cousin, Rohullah, had something else in mind.

The day before, the two men had gone to a bazaar area 3km away and rented a tiny, street-level shop. They told the owner they planned to sleep there instead of opening a business, so he could leave the windows covered, the police said.

On Sunday morning, Agha drove his motorcycle past Ahmadi's house; Rohullah, also about 18, was riding on the back. When they saw Mahsa emerge, they followed her for a while, then stopped and forced the little girl onto the bike between them, police said.

They drove her to the shop they had rented and hid her inside, according to police.

"It is weird that no one noticed her in that neighbourhood, it's a very busy bazaar area," said the police officer in charge of investigating the kidnapping, Mahmood Kochi, head of the 11th police district's criminal investigation division.

Neighbours around the bazaar district speculated that the men must have drugged her because no one heard her.

About 12:30 that afternoon, Ahmadi got a terrifying telephone call, according to his brother-in-law, Mohammed Abed Hamid.

"They asked for $300,000," he said. "Murtaza said he would sell his property and give them as much money as he could, but he pleaded that he could raise nowhere near that amount." Ahmadi begged them not to hurt Mahsa.

He hung up and called the police, and Kochi came right over.

"They kidnapped her because they wanted to get some money to go to Europe," Kochi said. Many Afghans pay people-smugglers thousands of dollars to get them to Europe, where they try to claim asylum.

"Poor man, his entire assets were $10,000," Aqa, the money changer, said of Ahmadi.

The kidnappers called back at 6:30pm, with the police listening in. Ahmadi pleaded for a lower ransom. "They said if Murtaza can give them $100,000, they will release Mahsa," Hamid said.

Suddenly, Ahmadi recognised the caller's voice.

In his shock and anger, Ahmadi called out the grocer's son by name, then said he had called the police. Perhaps he thought revealing that would save Mahsa; perhaps he couldn't help himself.

At 10 the next night, Mahsa's fully clothed body was found in a canal under a small bridge, not far from her home. She had been strangled.

"After we knew that her father went to the police, we decided to kill her," Agha later said in a statement to the police, officials said.

The police said they arrested the kidnappers the morning after Mahsa was found. Family members posted pictures of the girl, alive and dead, on social media, where the case quickly went viral.

The police released a video showing confessions by Agha and his cousin, delivered matter-of-factly, devoid of emotion or explanation.

"Even animals would not do what they have done," said Fraidoon Mahmoodi, a money changer and a friend of Ahmadi. "They killed her cruelly. The government should do the same to them."

Afghan social media has been filled with similar demands that the men be hanged, the country's usual method of execution. The outrage has spilled into the streets, too.

On a recent Saturday, Ahmadi went to Sarai Shahzada, the money market, where his colleagues were holding a one-day strike to demand swift punishment for the killers. He told the crowd how his daughter had been strangled with a scarf, then stuffed into a bag and dumped in a canal full of trash.

"Even an infidel would not do such a thing," he said.

Many of the money changers wept; Ahmadi spoke through his own tears. The last time he saw Mahsa alive, he said, he was headed to work when she asked him for a little money to buy a treat for her baby brother. He gave it to her.

"I dreamed of her last night, and she was saying, 'Father, don't cry this much for me.'"

Two weeks after the kidnapping, Mahsa's mother gave birth to another daughter. The parents named her Mahsa.