TOKYO — The light red flag with the five-petaled bauhinia flower does not represent a country. But Hong Kong, the Chinese territory where political and civil rights have been battered in recent months, is enjoying its strongest-ever showing at the Tokyo Olympics, capturing gold in fencing and two silvers in swimming.

The three-medal haul is the first time that Hong Kong, which was returned to Chinese rule by the British in 1997, captured more than a single medal at the Olympics. On Friday, the swimmer Siobhan Haughey won her second silver of the Games, in the women’s 100-meter freestyle, following a victory in the 200-meter freestyle event on Wednesday.

But out of the pool and off the fencing piste, Hong Kong’s fortunes have not been as bright. The territory was promised significant political freedoms for the 50 years after its handover to China, but Beijing has clamped down. Most of Hong Kong’s top opposition politicians are in prison or in exile. Last month, the biggest pro-democracy newspaper was forced to shutter.

On Friday, the first person to be convicted under a tough new national security law of terrorism and inciting secession was sentenced to nine years in prison for driving a motorcycle into police officers while carrying a protest flag.

Beijing’s crackdown has targeted contemporary art, civics lessons in high schools and children’s books featuring a dozen fluffy sheep.

“Currently, many Hong Kong people probably feel unhappy and full of negative emotions,” said Tse Ying-suet, who played in the bronze medal match in badminton mixed doubles on Friday. “I think athletes winning Olympic medals brings Hong Kong people some hope and joy.”

Tse and her partner, Tang Chun-man, went on to lose against a Japanese pair, but she thanked people in Hong Kong who had flocked to malls and other public spaces to watch the badminton contest live.

“I feel very happy that so many people got together to support Hong Kong athletes,” Tse said.

The Hong Kong police said on Friday that they had arrested a man in a crowd of people who had gathered to watch Cheung Ka-long’s fencing final at a mall. The man had violated the national anthem ordinance by holding up the British colonial flag and inciting others to chant negative slogans while the Chinese anthem was playing at Cheung’s victory ceremony, the police said. The authorities were also investigating whether he had breached the national security law.

“These insults to the Chinese national anthem are to incite hatred and politicize the sports event,” said Chung Lai-yee, a senior police superintendent.

Hong Kong first entered the Olympic fold in 1952 when it was a colony of the British, who ruled the territory with little regard for the rights of the colonized. At the 1996 Atlanta Olympics, Lee Lai-shan won Hong Kong’s first gold, in windsurfing. “God Save the Queen,” the British national anthem, was played at her victory ceremony. A colonial flag was hoisted.

Four years later, in Sydney, Hong Kong competed for the first time as Hong Kong, China. When Cheung won gold in fencing’s individual foil event on Monday, “March of the Volunteers,” the Chinese anthem, was played. The bauhinia flag was raised.

With the rapid erosion of Hong Kong’s freedoms, some have questioned how long the enclave will be able to field its own team at the Olympics. On Friday, Mark Adams, a spokesman for the International Olympic Committee, said that he was not aware of any discussion about Hong Kong’s future in the Games.

“I see no reason why it won’t continue,” he said.

During the Beijing Olympics in 2008, when equestrian events were held in Hong Kong, people in the territory cheered on both the Hong Kong team and the Chinese squad. Fears that Hong Kong would change drastically after the handover had not materialized.

The enclave, bound by a “one country, two systems” formula that ensured it a high degree of autonomy, seemed to enjoy the best of both worlds: a reputation as a law-bound society blessed with political freedoms and proximity to the booming markets of mainland China.

The last couple years have shattered that sense of security. Mass protests coalesced in 2019, bringing millions onto the streets. Each week seemed to bring more evidence that Beijing was determined to impose its will on Hong Kong. At the same time, some people in Hong Kong decried the pro-democracy movement, which disrupted the central financial district, calling it either impossibly idealistic or bad for business.

The trio of medals in Tokyo, an impressive tally for a territory of only 7.5 million people, has given the people of Hong Kong something to cheer.

Online, in English, the Hong Kong Olympic establishment celebrated the accomplishments of the medalists. But on one official website, the names of the athletes were at one point rendered in Mandarin, the official language in mainland China, not Cantonese, the predominant language in Hong Kong.

Ko Hei, a senior sports executive at the Hong Kong Fencing Association, said he was surprised to hear that Cheung’s name had been depicted for a time in Mandarin, rather than Hong Kong’s home language. (Cheung’s English given name is Edgar.)

Fencing has long been popular in Hong Kong, he said, and more than 1,000 children regularly turn out for competitions. The sport has garnered Olympic medals for China, too, including a gold in Tokyo.

“They’re getting very good,” Ko said, of China. “But we don’t have any relationship with them. We are separate.”

Joy Dong contributed research from Hong Kong.