Ukrainian National Army - Displaced person - POW Norfolk

I have been trying for a number of years to find out the details of my Grandfather.

He fought for the Ukrainian National Army (First Division I believe) in WW2 and was captured by the British in Italy/Austria and taken to a POW camp in Norfolk.

He then settled in Yorkshire.

I would love to find out more information about him either his military records or POW records. Can anybody help? I need to be able to get past this brick wall..>>!

Thanks!