Siobhan Haughey – the grandniece of former Taoiseach Charlie Haughey – won Hong Kong's first Olympic swimming medal by taking silver in the 200m freestyle.

The 23-year-old psychology major, already the first swimmer from Hong Kong to reach an Olympic final, looked set for gold before Australia's Ariarne Titmus chased her down.

Haughey's silver medal comes after Hong Kong secured a gold in fencing on Monday. It was Hong Kong's first gold medal in 25 years.

"My achievement, coupled with Cheung Ka-long in fencing, can inspire other Hong Kong athletes who are here in Tokyo, and 'add oil' to them," she said after her race, a phrase meaning to keep drawing strength.

"Those swimmers back home - continue to train hard and you will be the next."

Speaking to RTÉ Sport she said she was very aware of her Irish roots growing up and the family travelled to Ireland once or twice a year.

"I'm definitely aware of where I'm from but I think very fortunate growing up in Hong Kong but having very strong roots in Ireland," she said.

She said that while she considered competing for Ireland she was born and raised in Hong Kong and it "just makes more sense swimming for Hong Kong."

However, she said that she is looking forward to coming back to visit family in Ireland, including her sister who currently lives in Dublin.

Across the former British colony of Hong Kong, residents cheered and rejoiced after Haughey's stellar swim.

Shopping centres opened early to live stream the event, which took place at 9.40am local time, while some restaurants opened for breakfast to let diners watch before going to work.

Fung, a 70-year-old woman eating dim sum in a shopping mall in the city's Kwun Tong district, said she was thrilled with Haughey's silver medal.

"I feel very happy. I want to say continue to work hard, keep up the good work but we are already very satisfied."

Amateur swimmers celebrated her performance during morning training, brandishing posters of her name while others hit the city's bar district to watch and cheer with Hong Kong flags.

Haughey's mother is from Hong Kong and her father is Irish, the nephew of the late former Fianna Fáil leader (above).

She has shown massive improvement since her Olympic debut in Rio where she made the semis of the event and swam a time of 1:57.56.

And beating the likes of American Katie Ledecky and Italian Federica Pellegrini should give her confidence for the 50m and 100m freestyle events. She races in the 100m freestyle heats later today.

"I would like to thank my coaches in Hong Kong and the United States, and also my dad and mum, without them I would not be having such an achievement," she said.

Dublin Bay North TD Seán Haughey tweeted his congratulations, saying he was "so proud" of his cousin and praised her "huge sacrifices".