The Chinese unit of Sony Group Corp. has been fined 1 million yuan ($155,400) after its Japanese parent planned to release new products on the anniversary of the start of the Sino-Japanese War, according to Chinese authorities.

The Chinese market regulator said Sony's plan to release new products on the anniversary of the Marco Polo Bridge Incident on July 7 hurt the dignity of Chinese citizens.

Sony posted an advertisement online on June 30 saying it would release new products on July 7. After criticism grew in China, the Japanese company deleted the advertisement and apologized.

A skirmish between Japanese and Chinese troops near the Marco Polo Bridge in the outskirts of Beijing on July 7, 1937, escalated into full-scale warfare that lasted until Japan's surrender to the Allied Powers in 1945.

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