This is the story of 13 year-old Bernice, one of the many children in Ghana who have been driven away from parents too poor to care for them, ended up on the street with no education or money, and been recruited into Ghana's booming child sex trade.

Bernice's mother, a firewood vendor in a remote village in the rural northern Region of Ghana, sent her to the capital Accra after her father died when she was 11.

"I was not the first of my family to make the journey," she told IRIN. Her elder sister, who is seven years older, and a younger brother who is eight, were already there.

Bernice started off working alongside her sister as a porter, carrying heavy loads on her head and earning up to US$2 every day.

Later a friend introduced them to the owner of a brothel, an older woman who promised the girls they could make US$40 every night.

"The money was good so we decided to give it a try," Bernice said.

She had just turned 12 when she took her first client.

"It was very difficult and sometimes I cried after the night was over having slept some times with five guys and even on other nights six or eight," she told IRIN.

Bernice charged US$5 for a short bout of sex and US$10 for a longer bout, which could last from anything from 30 minutes to an hour. Most of her clients were boys in their teens.

"Some of the girls use drugs so they can have more men. I tried it once but it did not work for me," she said.

There are no figures on the exact number of child sex workers in Ghana but the Women and Children's Affairs Ministry estimates it is in the thousands.

Bernice and her sister were able to earn enough money to pay the owner of the brothel, who charged them US$10 for a night's rent of their adjoining cubicles, and to still have enough left to send home to their mother who Bernice said has "no idea" what kind of work her children are doing in the city.

Their work was recently curtailed when the Ghanaian police raided the brothel they work in, arresting all 160 of the prostitutes as part of a "war against child prostitution".

Their targets were the 60 girls among them who were under 16.