Hospital queried
Team GMP said Park passed doping controls during the Asian Games, contested at Incheon's Munhak Park Tae-Hwan Aquatics Centre, but failed a recent World Anti-Doping Agency (WADA) test.
"With our team of legal experts, we're trying to determine why the particular hospital injected Park with an illegal substance, and we're preparing to hold it civilly and criminally liable," the management agency said.
The revelation over Park comes after China belatedly revealed in November that double Olympic champion Sun served a three-month doping ban before the Asian Games.
China's Sun Yang presents South Korea's Park Tae-hwan (L) with a birthday cake at the Munhak Park Tae-hwan Aquatics Center during the 17th Asian Games in Incheon September 26, 2014. [Photo/Agencies]
The 1,500 metres world record-holder won three gold medals in Incheon after serving the previously unannounced ban. The failure was blamed on medicine for heart palpitations.
FINA executive director Cornel Marculescu declined to comment on Park to AFP, saying only that the world swimming body's anti-doping commission would meet in late February.
Park won 400m freestyle gold and 200m freestyle silver at the Beijing 2008 Olympics, becoming South Korea's first Olympic swimming medallist.
He also won silver in both events at the 2012 London Olympics, along with 400m gold in the world championships in 2007 and 2011.
But he had a disappointing time in the pool in front of an expectant home crowd at last year's Asian Games, managing only a silver and five bronzes.
The news could puncture some of the euphoria in South Korea on Tuesday after it came to light as the national football team reached their first Asian Cup final in 27 years.
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