The murderous math teacher of S-21

By Murray Bourne, 07 Nov 2011

The high school compound is quiet and peaceful. This is a neighborhood school, but lately there have been no neighbors, no teachers, and no students.

quiet and peaceful high school grounds

The whole city is quiet, since everyone has been sent out to the countryside in a weird "agrarian experiment". Everyone, whether they are teachers, bankers, artists or tuk-tuk drivers must now dig in the fields and grow rice. No one is left in the city. No one is spared, but that's all about to change.

The high school is being renovated. It's not to make things better for students, but to make it more convenient to inflict inhumane cruelty on hapless prisoners.

Classrooms are being modified by the construction of crude cells out of brick or timber. These will house prisoners who will suffer a hell of torture and torment, before eventually being taken to a nearby field and clubbed to death.

modified classrooms

Manacles are brought in, ready to constrain the 20,000 prisoners who will pass through this terrible place.


The first group of prisoners arrives by truck. Their crime? In many cases, they were arrested because they had the misfortune of being born in the wrong place or belonging to the wrong family, and being seen as potential traitors.

First stop is the photograph room, where each prisoner is assigned a number. This poor victim's number tag is crudely pinned to his skin.

number tag pinned to prisoner's skin

He's young, confused and very afraid.

The torture begins.

This exercise pole which used to keep young bodies healthy, is now the scene of unbelievable suffering.

number tag pinned to prisoner's skin

number tag pinned to prisoner's skin

Water-boarding was a common way of extracting "confessions". The prisoner was shackled by the feet at the higher end of the table and by his hands at the lower end. Water was poured onto his nose and mouth causing a drowning sensation.

water torture

Starvation and sleep deprivation added to the misery.


The prisoners who died during interrogation were photographed before their bodies were carted off in trucks.


The murderous math teacher

And who was running this terrible place?

Duch - murderous math teacher

Comrade Duch (real name Kang Kek Iew) ran the infamous S-21 Tuol Sleng prison camp in Phnom Penh during the insane Khmer Rouge period from 1975 to 1979.

Duch was an excellent math student, scoring second place in the Cambodia Baccalaureate in mathematics. He became a math teacher in 1966 and was a "good teacher. remembered as earnest and committed by his pupils".

After joining the Communist Party of Kampuchea (before the Khmer Rouge took over), he was arrested and tortured in prison because of his communist leanings. What a tragedy that he carried on such inhumane acts in his own institution, while in charge. This presumably became his "new normal".

He converted the Tuol Svay Prey High School into a place of brutality and cruelty. At the time, Cambodia had descended into a paranoid madness, modeled after the Cultural Revolution in China.

Detention and Trial

After the Vietnamese army invaded Cambodia and threw out the Khmer Rouge in 1979, Duch escaped to the Thai border, where he taught mathematics. He was a "good teacher, but one with a fiery temper."

Duch gave himself up in 1999 and was charged with crimes against humanity in 2007. The verdict handed down in 2010 concluded that he was guilty of crimes against humanity, torture, and murder. He was sentenced to 35 years' imprisonment.

Personal thoughts

I recently visited the Tuol Sleng Genocide Museum, which is at the site of the S-21 Tuol Sleng Prison. (All photos are mine.)

Tuol Sleng Genocide Museum

It was a deeply moving experience. There is so much tragedy in Cambodia's story but this is one onf the worst excesses of the period. The guards at this torture prison were often in their late teens. Here was a facility that was originally built to educate such people, but through collective madness, it was turned into hell and they were involved in perpetuating that hell.

One of the worst aspects of the "Democratic" Kampuchea period was that educated people were targeted for removal. A whole generation of teachers was killed, either through hard manual work, starvation, torture or execution. This has made the reconstruction of the country that much harder.

And yet, amongst the young people I met in Phnom Penh, there is a wonderful and refreshing thirst for knowledge. This bodes well for Cambodia's future.

I'm looking forward to doing some volunteer work in Cambodia over the next few years. There is certainly much to be done.

Final comment

I am disgusted to this day that waterboarding in US-run prisons was considered "acceptable" during the Bush years. Torture dehumanizes all those involved and rarely justifies the meagre outcomes.

See the 2 Comments below.

2 Comments on “The murderous math teacher of S-21”

  1. Philip Petrov says:

    There is a huge difference between S-21 Tuol Sleng and the US prisons.

    When the "khmer rouge" came at the head of Cambodia the situation was very difficult:

    1. At war with Vietnam;
    2. Absolutely no provisioning help from China - it was blocked politically by USA and England;
    3. No own food left and nobody to trade resources with (there was no resources anyway);
    4. The country was after war and practically with totally destroyed infrastructure (thanks to USA btw).

    I bet that even a saint will not be able to preserve the borders of such country without performing a war genocide. So whatever bloody massacre they did - it was in war conditions. Khmer Rouges was torturing people when they was defending their regime. That's not an excuse of course! But that's the fact which is making the picture a lot different than what is presented in the media.

    USA was (and continues to be) torturing people when they are attacking other regimes, not when they are defending themselves. USA people are not starving to death, they are not being attacked by much more powerful neighbor and they don't need any political protection.

    Do you feel the difference? The first one can be a subject of decision between nation survival and genocide. The second one is just a bloody aggression for more and more resources.

    P.S. I am not anti-capitalist, terrorist, communist, fascist or whatever usually the people with different thinking are presented in my country. But few things from the "European politics" in my country I cannot accept.

    For example the US embassy in Bulgaria made a "Memorial for the pilots and aviators who died during the bombing in Sofia during WWII".

    Guess what - there is absolutely NO memorial for the dead innocent Bulgarian civilians killed by the US pilots and aviators. There was 1828 civilians dead, 2372 irreversibly injured, 12000 buildings destroyed (most of them civilian houses). There was 19 schools destroyed, 14 churches destroyed, the National Theater destroyed... It's a shame for any army which should do that! USA must send to us excuses, not build monuments in the center of our capitol.

    How will you feel when a foreign country kill people and destroy buildings in your country, followed by building a monument about their loses? How will you feel when your own politicians say "we cannot build a monument of the civilian deaths during the bombings in WWII, because this will give a bad name to our new friends England and USA"... That's absolute insolence. That's an insolent demonstration of "look how powerful we are and how weak are you". That's a ridicule with whole nation which do not deserve it.

    Many Americans are very surprised when they hear that other nations are hating them. Why? You are living so well, you are "bringing democracy to other people" (with bombs??? LOL), so they can "live like you"?

    There are many things that we all must learn about history. You cannot call USSR "aggressor" for making 14 local wars in 45 years when at the same time the US made over 54 (USA have no year without war starting from WWII to today!).

    History is a very, very, very speculative thing. Either know it in details or never talk about it. Because if you just partially know history, if you just cite what the moderated Wikipedia says, if you never got in touch with the opinion of "the other side" - you can never know the truth.

    I don't hate Americans and USA. Don't get me wrong. They are doing what every empire was, is and will be doing.

    Your blog is awesome.

  2. ASTON says:

    glad to hear young cambodians thirst for knowledge. let's hope it's not a thirst for communism

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