A female journalist waved the colonial-era flag when celebrating Hong Kong's only gold medal at the Tokyo 2020 Olympics ©Getty Images

A female journalist has become the first person to be jailed for breaking Hong Kong’s national anthem law after waving a British colonial-era flag to celebrate Cheung Ka Long’s fencing gold medal at the Tokyo 2020 Olympics.

Paula Leung has been convicted for three months by Kwun Tong Court in Hong Kong after pleading guilty to the charge.

The 42-year-old online news reporter was spotted waving the British Hong Kong flag at a shopping mall during a screening of the Tokyo 2020 awards ceremony when Cheung collected his gold medal.

Cheung stunned Rio 2016 champion Daniele Garozzo of Italy to capture the men's individual foil title in the Japanese capital last year.

It was Hong Kong’s second-ever Olympic gold and first since its sovereignty was handed back to China by Britain in 1997.

Despite the handover, athletes from Hong Kong continue to compete separately from China but under the flag of the special administrative region of China.

Cheung Ka Long captured Hong Kong's first-ever Olympic fencing gold in Tokyo last year ©Getty Images
Cheung Ka Long captured Hong Kong's first-ever Olympic fencing gold in Tokyo last year ©Getty Images

The Chinese national anthem was also played when Cheung stood at the top of the podium after receiving his gold medal.

As the anthem rang out at the shopping mall, Leung waved the colonial-era flag while some booed and shouted "We are Hong Kong".

The National Anthem Ordinance law was enacted in June 2020, making disrespecting the Chinese national anthem a criminal offence with a punishment of up to three years in jail.

Magistrate Amy Chan Wai-mun said Leung’s flag-waving could have resulted in a "dangerous situation" with more than 1,000 people watching the broadcast of the medal ceremony and claimed that she arrived at the mall with intent to discredit the Chinese national anthem, as reported by the Hong Kong Free Press.