HYDERABAD, Pakistan - Ranjhan has spent 40 years working in a Pakistani brick kiln as a bonded labourer, tied to his employer by a debt his pitiful salary will never enable him to repay.
He is one of more than two million Pakistanis that campaigners say are trapped in "modern-day slavery", condemned to a lifetime of hardship and toil.
There are laws in place to outlaw bonded labour, but still the cycle continues, with thousands of children sucked in every year by their parents' supposed debts.
At an open-air factory on the edge of Hyderabad, around 150 kilometres (90 miles) north of Karachi, tall, tapering chimneys belch out noxious smoke.
Crouching children gather lumps of clay and pack them into rectangular moulds. On the ground, long rows of unbaked bricks wait to go into the kiln.
These are the scenes that have been the backdrop to Ranjhan's life since he was a child.
"I've spent the last 40-odd years in this grind, sometimes in one factory, sometimes in another," he said.
He works every day of the week at the coal-fired kiln, where 1,000 bricks will earn him around $2, every cent of which goes straight back to his employer.
"I borrowed 40,000-50,000 rupees (S$846 - S$1,058) to buy food for my children. I will never pay it back before I die - my debt will die with me," the father-of-three told AFP away from the eyes of his boss.
A global survey of slavery published last month by the Australian campaign group the Walk Free Foundation said Pakistan had the third most "slaves" in the world, after India and China, most of them working in brick making or agriculture.
Walk Free says the government needs to act to tackle the problem, including by regulating brick kilns and enforcing anti-slavery laws.
Wages go to boss
About the origin of his debt and that of his parents before him, Ranjhan says little.
From buying food to wedding dowries to hospital visits - there is no shortage of reasons why these impoverished workers would go to their boss for a loan which they can then never pay back.
Once the debt begins, the employer too has no shortage of reasons to keep adding to it - exorbitant charges for accommodation and food are typical - so the worker has no chance of ever paying it off.
"Everything we earn goes to our creditor who gives us food to eat," said Ranjhan.
Brick factories and farms across the country run on these workers, who are fed for a pittance on bread, lentils, oil, sugar and onions.
Some small trade unions are trying improve the situation, lobbying bosses to raise salaries to the equivalent of $5 dollars a day and not to trap their workers in the debt cycle.