Recently identified S-21 victim Christopher Edward DeLance. Photograph: Documentation Center of Cambodia

One of two Westerners whose portraits were found among a recently uncovered cache of S-21 inmate portraits has been identified as American sailor Christopher Edward DeLance, who was seized by the Khmer Rouge while boating off the Cambodian coast in 1978.

After receiving photographs of the two Westerners in a cache of 1,427 anonymously donated S-21 inmate portraits last month, Documentation Center of Cambodia director Youk Chhang suspected the two were DeLance and former Phnom Penh French Embassy employee Andre Gaston Courtigne.

To find out if one of the photos was DeLance, Youk reached out to author Peter Maguire, who researched the killing of Westerners at S-21 in his book Facing Death in Cambodia.

Maguire told Youk he had confirmed from two independent sources that the photo shows the face of DeLance.

Reached by the Post via email, yesterday, Maguire declined to comment about the case, citing respect for the families involved.

DeLance grew up in Long Beach, California, was married and had a daughter before he moved to Maui in the 1970s.

DeLance and three other Americans – Michael Deeds, James Clark and Lance McNamara – died after being imprisoned in S-21, a former high school that is now the Tuol Sleng Genocide Museum. They were tortured into confessing to working for the US Central Intelligence Agency.

Word of his death at S-21, where more than 14,000 people were killed under the Khmer Rouge regime, did not publicly come out until an American Broadcasting Corporation news story in 1979. Details about DeLance’s arrest by Khmer Rouge forces and imprisonment at the notorious Tuol Sleng interrogation facility are sketchy, based as they are on a lengthy and convoluted confession that was likely given under torture.

A copy of the confession, obtained by the Post, runs to 21 pages and was likely extracted over a longer period of weeks or months of a series of interrogations. The confession shows typically outlandish claims that were forced out of prisoners by Khmer Rouge officials.

DeLance’s is recorded as saying he posed for the CIA as a “hippie yachtsman”, used a job of delivering boats as cover, was tasked with spotting potential oil rigs so the US could establish corporate dominance in the region and, when he wasn’t busy with all that, looking into the military might of Cambodia.

“The CIA hoped to learn from the photographs and from our observations, the strength and the degree of military operations there. The CIA wants to know whether the majority of operations there are land or sea oriented (army or navy),” the confession reads.

According to DC-Cam, 11 foreigners from Australia, France, the US and New Zealand were killed at S-21.

Though the new information brings a partial end to the mystery, there is a second photo of a man yet to be identified. There are, to date, no significant clues.

Before hearing about DeLance, DC-Cam made several attempts at finding the truth about both Westerners.

Last week, its researchers were granted an interview with former S-21 chairman Kaing Guek Eav, alias Duch, to see if he could put names to faces. Duch, who is serving a life sentence for his role at S-21, failed to do so, repeating what he said on trial, that there were only four Westerners at the prison.

In August, DeLance’s brother told the US Defence Department’s Joint POW/MIA Accounting Command (JPAC), which tries to find Americans missing in conflict, he did not want to take part in the search.

Relatives and friends do not seem eager to revisit the past.

“Perhaps they’ve found a way to reconcile already,” Youk said, adding that his US citizenship made him feel a certain responsibility to find the truth about DeLance, a fellow American. “It may be difficult for the family to face, but I think it’s important to put this behind us.”

To contact the reporter on this story: Joseph Freeman at [email protected]