GENEVA (Reuters) -- Millions of child laborers and adolescent workers around the world face routine violence at their jobs, ranging from verbal abuse to rape or murder, the International Labor Organization (ILO) said on Monday.

In a report issued to mark United Nations' Universal Children's Day, the agency said the violence is often part of a collective workplace culture of physical brutality from which children employed in a workforce suffered most.

"For many child laborers, violence is a terrifying fact of daily life and must be stopped, together with child labor," declared ILO Director-General Juan Somavia in a comment on the report, which the agency said is aimed at ending the practice.

The ILO says there are some 218 million child laborers and some 100 million legally-employed adolescent workers around the globe. In some regions, it said, the majority of them encountered some form of violence or abuse.

Its researchers found that apart from verbal and physical abuse, they often faced "casual violence, including sexual harassment, and in extreme cases even rape or murder," according to the report.

Some groups of child and adolescent workers were especially at risk, it said, such as domestic employees, young people working in the informal economy, modern forms of slavery, and those doing dangerous work.

These last included those working in glass factories, mines, plantations and other agricultural establishments "where health and safety regulations are lax or non-existent," according to the ILO.