Thirteen-year-old Shivam Singh promised his mother he would be back to do his homework as he ran to get some sweets. He never returned, becoming one of the 50,000 children who go missing every year in India.
"My son left his books open, put on his sandals, combed his hair and ran out," Pinky Singh recalls tearfully of the fateful evening in July when Shivam popped out of the house. "It was the last time I saw him."
Three months on, perched on the edge of her son's bed and surrounded by his toys and sports trophies, Pinky Singh is terrified by what may have befallen him.
"I just pray that he is not forced into drugs or begging. He is a very innocent and studious boy."
According to recent crime data, 14 children go missing in New Delhi every day, at least six of whom are victims of human trafficking.
The United Nations Children's Fund (UNICEF) says around 1.2 million children are victims of child trafficking across the world every year.
India's mega cities such as Delhi and Mumbai are a particular target for criminal gangs that police say traffick children in much the same way they sell drugs.
In August this year, the country's top court ordered the federal and state governments to provide data on 50,000 missing children after a petition blamed them for failing to solve the trafficking of children by organised gangs.
Police officials said they have rescued hundreds of children from factories and busted large-scale child prostitution rackets but they accept they are sometimes overwhelmed by the scale of the challenge.
The country's federal detectives admitted last year that there were 815 gangs comprising of more than 5,000 members involved in the kidnapping of children for prostitution and begging across India.
"Very often we find kidnapped children are forced to work as cheap labour in factories, shops and homes. They get exploited as sex slaves or are pushed into the child porn industry," Delhi police spokesman Rajan Bhagat told AFP.
"These gangs target urban slum children because they can easily track their movement, lure them with food and kidnap them.
"Some poor parents are scared to even report the case to the police and most do not have photographs of their children to submit as an evidence," said Bhagat.
In 2006, body parts of 17 children stuffed in plastic bags were found by the police in Nithari, a suburb near New Delhi, a horrifying case that shocked the nation and triggered a raging debate on the safety of children in India.
Twelve-year-old Sharath Kumar knows better than most of the dangers that lurk.
The son of a small shopkeeper in New Delhi, Sharath was nine when he became a kidnap target while waiting to be picked up from school by his mother.
"The old man covered my face with a black cloth, he dragged me and threatened that he would kill me if I raised an alarm," said Kumar.
The abduction however was foiled when several youths heard Kumar crying out for help. They managed to rescue the youngster and reunite him with his mother.
"My son was just plain lucky. He was in a state of shock and cried for hours when he came home," said Kumar's mother, S. Laxmi.
The incident taught Laxmi a crucial lesson.
"When my son was kidnapped, the police demanded his latest photograph and I had nothing to offer. I kicked myself and cursed my husband for our carelessness," she told AFP.
She now gets portrait-size photographs taken of her two boys every six months.
Investigators say the absence of photographic evidence makes it impossible for them to trace the child.
"Most kidnappers target children aged between six to 13. We cannot trace the child without photographs," said V. Renganathan, a senior police officer in New Delhi.
Renganathan is the founder of an initiative called Pehchaan (Recognition) in which policemen take pictures of children in slum areas for their records and also provide copies to the youngsters' parents.
"The idea is to safeguard vulnerable children belonging to the poorer sections, millions of families in this country are too poor to even think about taking pictures," said Renganathan.
For Pinky Singh, who provided pictures of her missing son to the police, the wait for news just goes on.
"Every morning I wake up only to wait for my son's return and I fall asleep waiting for him. Waiting is the only way of life for me."