The 1st Infantry Division is a military formation of the Korean People's Army.
It was part of the North Korean advance from Seoul to Taejon.
The division fought in the Battle of Pusan Perimeter.
The intelligence section of U.S Far East Command headquarters listed the divisions order of battle as a 31 July 1952 as follows:
This same report listed the 1st Division as being in III Corps Reserve at the same time period.
References
1st Division (North Korea) Wikipedia(Text) CC BY-SA