Raphael Mutiku was warned about his personal and professional conduct but has strenuously denied using prostitutes

Oxfam has been engulfed by a second sex scandal over the conduct of its staff in earthquake-torn Haiti.

The charity put female aid workers and survivors of the disaster at risk by keeping a senior employee in the country for more than a year after realising that he was a sexual predator, according to an internal report obtained by The Times. It also appeared to have sanctioned prostitution.

Raphael Mutiku, who headed Oxfam’s team installing water supplies in Haiti after the earthquake in 2010, received a final written warning in June that year when he was accused of harassing female colleagues, the documents show.

Six months later it was alleged that Mr Mutiku, a Kenyan in his 40s, was paying young women for sex