Former volunteers spoke out about widespread sexual assaults they suffered while serving at the Peace Corps, and how the US aid agency had mishandled their complaints for decades.

Catherine Puzey said she lives "a heartbreak everyday" from the loss of her daughter Kate, who she said was murdered on her porch two years ago by a teacher at a school where she taught English in a remote village of rural Benin.

Kate had tried weeks earlier to warn the Peace Corps about the Beninese man, Constant Bio, who also worked for the agency during the summers and was already accused of sexually assaulting his students.

She emailed her boss but her complaint fell into the hands of the accused killer's brother, a deputy Peace Corps country chief. The 24-year-old was found with her throat slit just days later.

Her case is part of a growing number of former volunteers now opening up about their ordeals for the first time, sometimes decades later, triggering promises of legislation from lawmakers and of change within a Peace Corps at a crossroads half a century after it was founded by president John F. Kennedy.

Others spoke about how an agency where 60 percent of the staff are women made them feel responsible for getting raped.

About 200,000 people have volunteered for the agency in 139 countries in some of the most distant corners of the globe since 1961. Today, over 8,000 Peace Corps volunteers provide technical development assistance in 77 countries.

It's a thrilling experience for many of the volunteers, with an average age of 28, to help some of the world's most desperate people.

But over 1,000 of them reported sexual assaults in 2000-2009, including 221 rapes or attempted rapes, according to Peace Corps figures. The number is feared to be far greater due to the stigma associated with sex crimes.

After hearing emotional testimony in Congress from Puzey and three former female volunteers detailing sexual abuse by fellow Peace Corps workers and locals over several decades, the agency's director Aaron Williams vowed to end a policy of "blaming the victim."

"There is no doubt that what these courageous women have done has opened our eyes to what we need to correct and we need to correct it now," he told the House Foreign Affairs Committee. "Rest assured, this type of thing, blaming the victim, will not continue in the Peace Corps of today."

He outlined several reforms, including staff advising and advocating for victims, supporting volunteers after they leave the agency, updating volunteer and staff training and replacing a training tape that showed past sexual assault victims discussing their alleged missteps that led to the attacks.

The hearing was prompted by increased media coverage of the assaults, including segments on the women that ran in January on the ABC television programs "20/20" and "Good Morning America."