The USS Panay incident was a Japanese attack on the American gunboat Panay while it was anchored in the Yangtze River outside Nanking (now spelled Nanjing), China on 12 December 1937. Japan and the United States were not at war at the time. The Japanese claimed that they did not see the American flags painted on the deck of the gunboat, apologized, and paid an indemnity. Nevertheless, the attack and the subsequent Allison incident in Nanking caused U.S. opinion to turn against the Japanese.