Angelina Jolie has long been a fan of Cambodia having adopted her eldest child, Maddox, from the country. Following repeated trips to his South East Asian birthplace, the actress and director recently embarked on a biographical thriller based on the Khmer Rogue‘s brutal regime - First They Killed My Father: A Daughter of Cambodia Remembers.

Angelina JolieAngelina Jolie has come under fire for the casting of orphans in her new film

However, the star, and the film's casting directors have come under recent fire for the "traumatic" audition process for orphans cast in the film.

Child actor Sareum Srey Moch was discovered to play the lead role the film - but Jolie revealed that the audition process was a cruel game.

During an interview with Vanity Fair, director Jolie, 42, said how she searched "orphanages, circuses, and slum schools" for the perfect star.

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She claimed she would put money on the table in front of the impoverished child she wanted to audition, ask what they would use the money for, then snatch it away.

It was revealed the "director would pretend to catch the child, and the child would have to come up with a lie."

Jolie added: "Srey Moch [the girl ultimately chosen for the part] was the only child that stared at the money for a very, very long time.

"When she was forced to give it back, she became overwhelmed with emotion. All these different things came flooding back.

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"When she was asked later what the money was for, she said her grandfather had died, and they didn’t have enough money for a nice funeral."

The Lara Croft actress, who is currently going through a divorce with Brad Pitt, also revealed the locals didn’t know she was filming the biopic.

She said: "When the Khmer Rouge came over the bridge, we had a few people who really dropped to their knees and wailed. They were horrified to see them come back."

It is believed as many as two million Cambodian nationals were killed between the years of 1975 and 1979 during conflict and the control of the Khmer Rouge regime.