pow camps ww2 grandad held by japanese

Hi,
I am researching my grandad edgar rhodes born 1915 bradford, yorkshire.
Moved to Essex area and resided there until death.
The only thing I have heard about his war service time is that he was evidently held captive at a prison of war camp by the Japanese. I don't know when or where, and I don't know when he was released, only that he was released and evidently could not walk as he was placed in a small area where he couldn't stand and he was very underweight.
Is there a way I can find anything out about him.
Karen

I do know other information as in marriages where he lived and so forth, but looking for war info.

I assume that he was a serviceman? Army?
(The Japanese had many civilian prisoners as well).

Below is a link to the National Archives research guide which hopefully will help you:

https://www.nationalarchives.gov.uk/...ar-korean-war/