By Deutsche Presse Agentur
In a survey of 50 individuals employed at 11 production sites, all but one owed their factory between 1,000 to 6,000 dollars, a study by the Cambodian League for the Promotion and Defence of Human Rights (LICADHO) found.
The practice, commonly known as debt bondage, sees a person pledging labor or services as security for the repayment of a debt or other obligation.
On average, employees were found to owe between 2,000 and 3,000 dollars.
Cambodia's average national income was 1,159 dollars in 2015, according to the World Bank.
"Debt bondage and child labour are rife in Cambodia's brick factories, many of which are in plain sight just a few miles from the capital city," Am Sam Ath, LICADHO's Monitoring Manager, said in a statement.
"The authorities know exactly what's going on inside."
In many cases, LICADHO found that loans from informal lenders were transferred to factory owners to pay off a debt.
The study also found that children were working alongside their parents in the factories in some instances.
Minister of Labour Heng Sour told dpa his ministry was unaware of the situation but would "follow up on it." "Cambodia has strongly committed to zero tolerance of child labour and we have a child labour department within our ministry," he said, before adding that the definition of child labour is more lax in Cambodia, as children over 15 are allowed to work in most industries.