The prisoners were 'looked after' by both Japanese and Korean guards. They were taught early on in their military careers that to surrender was dishonest, and that any prisoners would be tortured and murdered by their captors. They were high on discipline, but lacked in basic training and weapon handling, and were subjected to frequent beatings by their superiors. It is no wonder then, that they passed this treatment onto their prisoners, who were seen as 'less than human' due to their surrendering.
The Korean guards were volunteers, who treated the prisoners worse than the Japanese as they were 'less civilised', and the Japanese had a 'higher norm'.
Beatings were a regular, everday occurance duing the duration of the building of the railway, bamboo rods, rifle butts, and burning cigarettes being the favoured form of punishment. Punishments would occur for anything, from not working fast enough, to looking at the guards the wrong way.
Tokyo had never given any guidelines as to how prisoners should be treated, and had no idea how to cope with the thousands of prisoners after the allied surrender. This is not an excuse for their actions, but an insight into their behaviour towards the prisoners.
After the war most of the guards were court marshalled, and all were given prison sentences, 2 being executed. See the 'Aftermath' page for more.