Bôrô no kesshitai (1943)

Summary from IMDb:
The story centres around a border security team in 1935 Korea. Upon receiving new recruits they hold a welcome party including a restaurant owner and his daughter. The border’s commander has a wife (Hara Setsuko) who helps deliver a neighbour’s baby. One day a border guard is killed by a Chinese bandit who is hiding in the area. The dead man’s sister comes to visit and is given help to further her studies. The film was shot in Korea featuring many Korean actors and crew.