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By Brenda Goh
RIO DE JANEIRO, Aug 8 (Reuters) - A Chinese state newspaper described Australia as "uncivilized" and "Britain's offshore prison" as it rushed to the defence of champion swimmer Sun Yang, who was labelled a drugs cheat by Australian rival and gold medallist Mack Horton.
The row, which started at the Rio Games with a friendly splash in training between the two arch rivals, is turning into a battle of national media commentators and underlines how the issue of doping has become a defining issue for these Olympics.
The Global Times, an influential tabloid published by the ruling Communist Party's People's Daily, said Horton had shown a lack of respect to Sun and "cynical smugness" after beating the Chinese swimmer in the men's 400 metres freestyle final.
Sun, who finished second, was revealed two years ago to have secretly served a three-month suspension for using a banned stimulant. He said at the time the stimulant was in medication to treat a heart issue and did not enhance his performance.
Horton first described Sun as a "drug cheat" in an interview with Australian media on Saturday, hours ahead of the final, and has since stuck by his words, including at a post-race news conference while seated right next to Sun.
"It's not a big deal to us. In many serious essays written by Westerners, Australia is mentioned as a country at the fringes of civilization," the Global Times said in a commentary.
"In some cases, they refer to the country's early history as Britain's offshore prison," it added, referring to Australia's past as a British penal colony.
"This suggests that no one should be surprised at uncivilized acts emanating from the country. We should think the same way," it said.
Horton told the Sydney Morning Herald that he had made his comments to unsettle Sun, who was the London 2012 defending champion, but that the description was accurate.
Furious Chinese fans have bombarded Horton's Facebook and Instagram accounts, demanding he apologise.
Chinese state newspaper China Daily said the International Olympic Committee (IOC) was looking into Horton's comments, but an IOC spokesman said it had no plans to investigate.
"People say many things in competition,. At the moment we had no complaints from anyone for any leads to follow up on," the spokesman said.
Australia's Daily Telegraph defended Horton in a Sunday editorial, saying he should rejoice in the rage of Chinese fans "who don't seem to accept that their hero has a documented involvement with illegal drugs".
The Global Times said that Australia should feel embarrassed with Horton's remarks: "If Horton won the competition by disrupting his rival in an immoral way, his win is disgraceful, and not in line with the spirit of the Olympics."
The online row has also been felt elsewhere. A man named Mark Horton from Watford, England, tweeted that he had received more than 200,000 mentions and online abuse after being mistaken for the Australian swimmer on Twitter. (Additional reporting by Karolos Grohmann; Editing by Mark Bendeich)