HONG KONG (BLOOMBERG) - Hong Kong police have arrested a man on suspicion of insulting the Chinese national anthem at a shopping mall in the city during the broadcast of an Olympic gold medal ceremony for a local fencer.

The incident occurred as hundreds gathered on Monday (July 26) at a mall in Kowloon to watch a live broadcast of an awards ceremony, according to senior superintendent Eileen Chung Lai Yee of the Crime Kowloon East Regional Headquarters.

The police said they received complaints that some people booed during the award ceremony when China's national anthem was being played, according to local media. Some shouted "We are Hong Kong", The South China Morning Post reported on Friday.

Fencing athlete Edgar Cheung received a gold medal, the first for the city since the 1996 games in Atlanta. Since Hong Kong is part of China, the Chinese anthem was played.

The 40-year-old man, who described himself as a reporter, was detained for investigation after holding a flag from the British colonial era, booing, chanting slogans and inciting others to insult the national anthem during the event, she said.

Under the city's year-old national anthem law, it is illegal to denigrate the Chinese national anthem. It carries a penalty of as much as HK$50,000 (S$8,708) and three years of imprisonment upon conviction.

Hong Kong police said they found 10 colonial flags of different sizes in the man's possession. They said they were checking to see if there were others in the mall who incited others or if anyone breached the national security law.

The arrest took place on the same day a Hong Kong court sentenced the first person convicted under the Beijing-drafted security law to nine years in prison, a ruling that illustrates the high stakes facing dozens of pro-democracy activists awaiting similar trials.