A current volunteer for the United States’ Peace Corps program in Cambodia lived with alleged Khmer Rouge war criminal Meas Muth for several months last year as part of his official service in Battambang’s Samlot district, the program has acknowledged.

Muth, 76, lives freely despite being charged in Case 003 by the Khmer Rouge tribunal for allegedly executing, enslaving and torturing enemies of the regime, including many foreigners, during his time as one of the Khmer Rouge’s top commanders.

But that history didn’t stop the Peace Corps from selecting Muth’s son, Meas Sophors, as the host “father” for volunteer Ben Larracey in 2013.

Peace Corps host families are paid, which means the federally funded program compensated Muth’s family a little over $100 a month for almost two years.

Larracey settled into Sophors’ house at the start of his two-year service in September 2013, moving in with Muth only a few months later at the start of 2014.

Larracey has since returned to live with Muth’s son, who remains close to his father and lives in the same remote district.

In an interview at his home last week, Muth said he allowed the volunteer into his family because he no longer had any desire for revenge against his former “enemy”.

“I have not forgiven my enemy, but my enemy does nothing to me [now], so I will not do anything back against them,” he said as he puffed on tobacco wrapped in leaves under his stilted house in Samlot.

While Muth said the volunteer only stayed at his son’s house, it is well-known in Samlot that a Peace Corps volunteer once lived at Muth’s nearby home for reasons that remain unclear.

Larracey and Sophors both declined to comment for this story.

According to Hout Sokhom, the director of the Samlot high school where Larracey had taught English as part of his service, the volunteer lived with Muth while his son’s house was undergoing repairs.

Larracey was due to finish teaching at the school in July, Sokhom said.

Former Battambang Peace Corps volunteer Nicholas Branch remembers visiting Larracey at Muth’s house one day in the summer of 2014, “six or seven” months after Larracey began living there.

Branch said he was performing a site visit with Alissa Bellot, Peace Corps Cambodia’s director of programming and training.

“Every Peace Corps person gets their site visited just to see how they’re doing,” Branch said, adding that he and Bellot met Muth during the visit.

Branch described the alleged war criminal as “a very quiet guy”.

Bellot did not reply to later questions about the site visit, but had previously said that “we have a very extensive vetting process for all of our homestay families”.

When asked for comment, the Peace Corps office in Washington, DC, did not explain why a volunteer once lived at Meas Muth’s home and was hosted by Muth’s family.

Nevertheless, the Peace Corps said it had taken quick action following the enquiry, removing Larracey from the family of Meas Sophors on Thursday and saying it would re-examine its procedures.

“As soon as Peace Corps Headquarters learned of this situation, immediate action was taken and the Volunteer in question was removed from their site. Peace Corps will review its processes, as volunteer safety and security is the agency’s top priority,” a statement from a Peace Corps spokesperson reads.

“Peace Corps takes the responsibility to place volunteers in safe and productive homestays extremely seriously.”

When he was visited last week, Muth said Larracey’s stay came out of a new-found good will towards his former sworn enemy.

“If they agree to give me happiness, I can also give happiness back.”

According to Muth, Larracey would periodically come to visit his house on Saturdays while he lived with his son, and eat jackfruit or durian – although the volunteer always paid for the fruit.

“I am a man who does not like to talk much, so I just say ‘hello’ and ‘how are you?’ in the Khmer language to him.”

On March 3, Khmer Rouge tribunal investigating judge Mark Harmon charged Muth in absentia with “murder, extermination, enslavement, imprisonment, persecution on political and ethnic grounds, and other inhumane acts” for actions the former navy commander allegedly committed at the S-21 and Wat Enta Nhien security centres, on islands, and at sea.

Although Meas Muth is wanted by the ECCC – of which the United States is a major donor – he has never been put on trial for his alleged crimes due to vociferous opposition from Prime Minister Hun Sen, who has said prosecuting any cases beyond the current Case 002 would foment a “civil war”.

Earlier this month, documents released by the ECCC revealed that Cambodian judicial police had failed to act on a December arrest warrant issued to bring Muth to trial, prompting renewed allegations of government interference in the court’s proceedings.

Muth’s defence, however, in a statement released on Friday, rejected the legitimacy of the warrant, saying it is invalid because it lacks the signature of Harmon’s national counterpart, You Bunleng.

It remains unclear exactly how the Peace Corps allowed a volunteer to stay with a highly politically sensitive alleged war criminal, especially as the United States says it “long supported the goal of prosecuting those most responsible for the atrocities perpetrated by the Khmer Rouge regime” in a statement from its embassy last August.

But the ball may have started rolling with Lot Bunthoeun, who lives close to Meas Sophors’ house.

Bunthoeun said he had been approached by the US Embassy to host a Peace Corps volunteer, but he declined the request as he was moving soon.

He referred them to Sophors’ house instead.

“The condition of renting the house was to provide food for Peace Corps in the evening, and [in return] they give us $110 per month,” he said.

The first group of Peace Corps volunteers arrived in Cambodia in 2007, according to Peace Corps Cambodia’s website. Since then, over 300 volunteers have served in the country.

“Living with a family helps our volunteers integrate into the communities in which they work, study local culture and traditions, and learn to speak Khmer, the local language,” the site reads.