TAIPEI, Taiwan (AP) -- Hong Kong police have arrested a man accused of booing the Chinese national anthem while watching an Olympic event at a mall.

The 40-year-old man was allegedly waving colonial-era Hong Kong flags and booing, while urging others to join him in insulting the national anthem, according to a police statement posted on Facebook.

Hong Kong passed a law in June last year that criminalized any actions that insult the national anthem. Violating the law can mean a fine of up to $6,400 (50,000 Hong Kong dollars), and up to nine years in prison.

China's central government criminalized actions that insult the national flag and emblem in amendments to the law last October, which is also applicable to Hong Kong, a former British colony.

The suspect was standing in a crowd with others on Friday to watch Hong Kong fencer Edgar Cheung in a match that would win him gold, local media reported.

The booing started at the medal ceremony, when the national anthem began playing.

Police said there may be additional arrests and that an active investigation is underway.

Hong Kong was rocked by months of sometimes violent anti-government protests in 2019, which led Beijing to crack down on dissent, including arresting leading pro-democracy activists in the city