For a young Chum Mey, “CIA” and “KGB” were nothing but meaningless clumps of letters, spat at him again and again during interrogations at the Khmer Rouge’s notorious Tuol Sleng prison.

But after 12 days of torture – during which he was beaten with a stick, had two toenails extracted, had a finger broken and was electrocuted twice to the point of losing consciousness – Mey put his thumbprint to a document confessing he belonged to both international spy agencies.

Mey, now 82, is one of only two remaining survivors from the handful that escaped the grim halls of Phnom Penh’s S-21 prison – also known as Tuol Sleng – and was called to testify before the Khmer Rouge tribunal yesterday in the ongoing Case 002/02 against former leaders Nuon Chea and Khieu Samphan.

S-21 was a security centre at which more than 12,000 prisoners, many of them Khmer Rouge cadres, were tortured by the regime into signing false confessions before being summarily executed, and survivors’ accounts abound with descriptions of inhumane acts.

Mey himself had already testified in the court’s Case 001 against S-21 prison director Kaing Guek Eav, better known as Duch.

Senior assistant prosecutor Vincent de Wilde asked Mey if he was ever treated “like a human being, with respect and dignity” in the prison.

“At the time I was considered a traitor, I was regarded as an animal,” Mey said.

He described how prisoners were shackled at the ankles and forced to urinate into a small repurposed ammunition box. “When we relieved ourselves, either urinating or excrement, if our waste spilled onto the floor … we were required to lick with our tongue until the floor became clean,” he said.

Mey’s mechanic skills, however, proved useful to the prison guards – since he was able to fix their typewriters, he was kept alive.

Prior to his imprisonment at Tuol Sleng in October 1978, under the false pretense of being transferred to repair vehicles in Vietnam, Mey repaired sewing machines for the regime’s textile unit at Phnom Penh’s O’Russey Market where he caught a fleeting glimpse of former Khmer Rouge head of state Khieu Samphan.

“I did not dare to talk to him, I did not even dare to approach him,” Mey said.

Mey, who now frequents the former prison and sells his autobiography to tourists, lost his immediate family to the regime, with his wife and newborn child shot dead just after his escape after January 7, 1979.

Nuon Chea defender Victor Koppe probed Mey on his time at the prison, noting the absence of his mug shot at the S-21 museum.

He also asked why Mey did not testify at the 1979 People’s Revolutionary Tribunal – often dismissed as a show trial – that found Pol Pot and Ieng Sary guilty of genocide in absentia, whereas fellow mechanic and S-21 survivor Ung Pech did.

Koppe asked Mey for an explanation as to why Pech – whom Mey claimed he knew well as they had escaped together – did not mention Mey when he listed only four survivors of S-21 at that trial.

Mey’s testimony will continue today.