Scandal-hit British charity Oxfam was reeling Tuesday after fresh claims of sexual assault and cover-up in South Sudan, as Haiti's president condemned the behaviour of some of its staff in his country as "undignified and dishonest".
Helen Evans, former global head of safeguarding, also warned of assaults on children volunteering in Oxfam's hundreds of high-street charity shops in Britain.
She accused senior managers of failing to act, heaping pressure on chief executive Mark Goldring just hours after his deputy resigned over a scandal involving aid workers' use of prostitutes in Haiti and Chad.
Haitian President Jovenel Moise spoke out about the scandal on Tuesday saying there was "nothing more undignified and dishonest" than humanitarian aid workers exploiting "needy people".
Evans told Channel 4 News of a survey conducted during her 2012-2015 tenure which exposed a "culture of sexual abuse" in some Oxfam offices.
The survey of 120 staff across three countries found between 11 and 14 percent said they witnessed or experienced sexual assault.
Seven percent of staff in South Sudan -- four people -- witnessed or experienced rape or attempted rape involving colleagues.
The revelations have caused outrage in Britain, where Oxfam received £31.7 million (35.7 million euros, $43.8 million) from the government last year.
Some commentators have said the scandal should prompt a rethink of Britain's commitment to spend 0.7 percent of its national income on foreign aid -- a UN target that only very few countries in the world respect.
'Scope for abuse'
The international development ministry has begun a wider review of how the foreign aid sector deals with allegations of sexual misconduct in the workplace.
"Emergency situations are almost a perfect environment for these kind of activities to emerge," Mike Jennings, head of the Department of Development Studies at the University of London's School of Oriental and African Studies, told AFP.
"You have extremely vulnerable people... and a few people who are effectively controlling access to resources, or have huge amounts of power.
"Whenever you have those inequalities and variances in power, you have scope for abuse."
Megan Nobert, who was drugged and raped by a fellow aid worker in South Sudan in 2015, told BBC radio that sexual violence in humanitarian workspaces was a "common occurrence".
She drew parallels with the #MeToo campaign of denouncing sexual harassment, which started in Hollywood and has since expanded to different sectors such as the media, politics and the world of music.
"The humanitarian community is the latest to have to grapple publicly with an issue that it's been trying to figure out how to respond to quietly," Nobert said.
Sex for aid
Evans said she asked to take her findings about abuse to the senior leadership team at Oxfam, but the meeting was cancelled and Goldring told her that discussing the report would not take things any further.
Later during her tenure, Evans said she received three new allegations in a single day in February 2015, including one woman forced to have sex for aid.
"There was one of a woman being coerced to have sex in a humanitarian response by another aid worker, another case where a woman had been coerced to have sex in exchange for aid, and another one where it had come to our attention where a member of staff had been struck off for sexual abuse and hadn't disclosed that," she said.
Evans -- now a local councillor in England -- said she "struggled" to understand why senior management did not give her more resources to address the problem.
In a separate issue, Channel 4 cited figures showing seven incidents of "inappropriate conduct with children" in Oxfam's shops in 2013/14.
One case involving an adult volunteer assaulting a child -- the minimum age for volunteers is 14 -- went to court, Evans said.
Oxfam has been battling accusations it covered up allegations about the use of prostitutes by Oxfam staff members in Haiti following a devastating 2010 earthquake.
Following an internal investigations, some staff members were dismissed and others allowed to resign.
But the charity has admitted it could have been more transparent with regulators about the accusations.
Oxfam deputy chief Penny Lawrence resigned on Monday, saying: "As programme director at the time, I am ashamed that this happened on my watch and I take full responsibility."