South Korea's players celebrate after winning their men's soccer bronze medal match against Japan, in Cardiff, Wales, at the 2012 London Summer Olympics, Friday, Aug. 10, 2012. South Korea won 2-0. (Photo: AP)
The International Olympic Committee says it has opened its own investigation into the incident during Friday's match.
The IOC says in a statement Saturday that "we have opened an inquiry and have asked the (South Korean Olympic committee) for an explanation."
The match in Cardiff, Wales, was seen as potentially raising diplomatic tensions between South Korea and Japan.
A South Korea flag with a slogan supporting sovereignty of disputed islands was reportedly displayed on the field.