An art exhibition featuring watercolors by the late Sadamichi Hirasawa, who was sentenced to death over a 1948 mass-poisoning case known as the Teigin Incident, will open Saturday at the Otaru City Museum of Art in Hokkaido.

The highly acclaimed artist lived in Otaru, known for its canal, during his youth and influenced local watercolor painters there before his arrest over the notorious incident in which 12 people were poisoned to death at a Teikoku Ginko (Imperial Bank) branch in Tokyo.

"While it has been known that the art world in Hokkaido was created by those who were trained by Hirasawa, we could not present the historic fact through his real works" because many of them were scattered and lost following his arrest, said the museum's curator, Nanae Hoshida.