On February 23, 1938, the Russians bombed Taipei. Given how worried the government was about Taipei being bombed by communists when I was first there in the 80’s I am somewhat surprised that I had not heard about it before. (( I found this account, based on Russian sources, in 汪金国, 反法西斯战争时期的中国与世界研究胡德坤主编第八卷战时苏联对华政策, 武汉大学出版社，2010 )) To celebrate Red Army Day 28 planes crewed by the Russians who were serving in the Chinese airforce attacked Songshan airport outside Taipei. Having received reports from Russian intelligence on the state of the airfield, the Russian commander波雷宁 led his planes to Taipei. They managed to locate the airfield through the clouds, and as the Japanese assumed they were friendly they were not fired on. He reported that they bombed the planes, the airstrip, and the hangars. Given the lack of response they then strafed the area. According to later sources 12 Japanese planes were destroyed, and a few people killed. The head of the Chinese Air Force reported that this made news all over the world, including Japanese radio (showing how important to him the propaganda side of this was) and that the Japanese commander promptly committed seppuku. He also told the pilots that they had proven that Russia was giving China real aid, not just words.
Without much effort I found a few brief press accounts of the attack, none of which mention the Russians, attributing it all to Chinese planes, and none of which, naturally, include anything like interviews with the pilots, who might have become national heroes if they were Chinese.
Shen Bao reported that “flames and smoke reached up to heaven,” something that lots of Chinese could probably picture at this point, and reported from Japanese papers that 40 planes were destroyed, along with fuel, repair shops and about 100 people were killed.
New York Times thought that it was just a random bombing of the city, rather than a military attack, but did claim that it showed that China was not about to surrender. Latter in the week they would report that sightings of Chinese planes over Hangzhou would lead to alerts in Taipei and elsewhere, so if the goal of the attacks was to encourage future Japanese over-reaction it worked well.
Da Gong Bao (Hankou) reported it as the first strike outside the country (空军出国第一功) so apparently they were of the opinion that Taiwan is not part of China.
All in all a glorious bit of Chinese military history, if only it had been more Chinese. One presumes it helped Chinese morale, and taught the Japanese the surprise attacks can work really well if you catch the other guys napping. Plus its just an odd bit of history.