A British woman has denied enslaving three girls and forcing them to work for up to 20 hours a day in horrific conditions.

Mercedes Farquharson, 63, is alleged to have banned the girls, who were not her natural children, from going to school or having friends.

Charges said she forced them to perform physical labor in harsh conditions at her house in Monroe, North Carolina, in the United States.

They had been forced to work or face beatings from as young as seven, prosecutors said.

They allege the girls were also made to clear up after dozens of animals including chickens, dogs and sheep.

One of girls was Farquharson's adopted daughter, while the other two were taken from Southall, west London, in the 1990s while their real mother was struggling with her marriage.

The girls were rescued in 2005 at the ages of 15, 18 and 22 following complaints from neighbors of suspicious activity at the house.

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