An undercover investigation into the world's largest electronics company, Samsung, by the human rights organisation, China Labour Watch, has revealed that abuse of workers is rife in factories, either owned by Samsung, or in those that make parts for Samsung products.

Eight factories were investigated - including six directly operated by Samsung and two supplier plants - by spies, posing as workers or interviewing workers, where they found forced and excessive, child labour, overtime, exhausting working conditions and widespread verbal and physical abuse.

As news of the report surfaced, the BBC approached Samsung for comments on the investigation findings.

A Samsung spokesman responded by saying: "We frequently review our manufacturing facilities regarding overtime work. When new production lines are completed or new products are launched, high demand has led to overtime work." The South Korean firm then said it would re-evaluate working hours.

Written and presented by Ann Salter.