Many girls involved in child labour undertake similar types of work as boys, but often endure additional hardships and face extra risks.
A major sector of employment for young girls is domestic work in households.
In Bangladesh, an estimated two million domestic workers are employed in the cities of Dhaka and Chittagong alone.
According to rights groups in the country, the girls often begin working when they are eight-years old and can be subjected to violence and sexual abuse.
The Bangladeshi Labour Institute says there are approximately eight million children who have full or part-time jobs.
However, in a country where at least 40 per cent of the population lives in poverty, child labour is often regarded by many as a necessity.
The ILO has called for a "policy response" to address the causes of child labour, such as high poverty rates in developing countries.
"Investing in girls' education is particularly important," Thijs said.
"Putting girls into schools is one of the best investments any country can make."