A fresh report by Save the Children and the High Commissioner For Refugees has revealed how aid workers

Daily Mail reports that the humanitarians exchanged wheat and life-saving medicines for sex with children as young as 13-years-old in crisis zones that include Guinea, Liberia and Sierra Leone.

The UNHCR UN Refugee Agency, report also revealed that officials knew of the alleged abuse in Africa long before the Oxfam sex scandal in disaster-struck Haiti in 2011.

Over 40 aid agencies working in West Africa were named in the report along with 67 individuals.

How girls traded sex to get income for family

The report published in Daily Mail revealed that underage girls were asked to pose naked for pictures and rooms were rented for sex and exploited in other to get income.

It was further reported that the aid workers also traded 'oil, bulgur wheat, tarpaulin or plastic sheeting, medicines, transport, ration cards, loans, education courses and skills training' with girls aged 13 to 18.

It was also reported that in some cases, some parents encouraged their daughters to be sexually exploited by aid workers, government officials, UN peacekeepers, refugee leaders and teachers to bring income into the family.

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The probe shows the abuse on young girls were rife in Guinea, Liberia and Sierra Leone.

'The children themselves, whilst aware of the exploitative nature of the exchange, felt this was often the only option they had in order to receive food and other basic necessities and to pay for education.

'Parents were often aware of the exploitation but also felt that there were no other options for their family to secure a livelihood and whilst not approving it, generally turned a blind eye.

In some cases, however, it was reported that parents encouraged their daughters to engage in such activities to bring an income into the family' it says.

Aid workers withheld provisions till girls gave sex

The probe also revealed that while security forces pooled cash to have sex with children, aid workers withheld provisions for children unless sex was given.

A refugee in Guinea revealed how aid workers would ask for sex in exchange for a kilo of soya nutrients.

In the same vein, a teenage girl in Liberia said: 'It's difficult to escape the trap of those people. They use food as bait to get you to have sex with them.'

The probe also revealed that majority of the abused children consulted said they knew of at least one other child involved in an exchange that involved trading sex for food or medicine.

The probe also alleges agency workers ask girls for sex in 'exchange for employment and continued to demand sexual favours after employment'.

A female agency worker in Guinea said 'No girl will get a job without having sex with NGO workers. The girls see it as competition. It is survival of the fittest'.

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How girls under 12 were constantly harassed

The probe revealed: 'Girls between the ages of four and 12 were also reported as being sexually harassed, either verbally or through touching of buttocks, breasts, or genitals. Children said boys of their age group also did the same, but that adult males were mostly responsible.

'Children reportedly experience attempted rape mostly when they go to use the toilets or take a bath. The toilets and bathrooms are all located in the same place, and divided along gender lines. Children say adult males lay watch for when the child is going to the toilet. They then follow the child and try to rape them.'

The report also explains that the children are aware of the exploitation, but often feel they have no other options.

The investigation also found that sometimes younger girls were befriended so aid workers could gain access to their mothers or older sisters, and some teenage boys were also exploited by older women.

Senior staff aided humanitarians commit impunity

The study of more than 1,500 people revealed that senior staff often allowed agency workers to 'behave with impunity' and that aid workers were 'most frequent sex exploiters of children, often using the very humanitarian aid and services intended to benefit the refugee population as a tool of exploitation'.