Japan’s professional soccer league on Monday said it was investigating after a banner reading: “Japanese only” was displayed at a weekend match.
The large banner, written in English, was hoisted near a gate to the stands of a stadium in the city of Saitama near Tokyo, where home club Urawa Red Diamonds were taking on rivals Sagan Tosu.
Social media was abuzz with speculation that the sign could have been targeting South Korean-born striker Tadanari Lee, who was released by English club Southampton for a transfer to Urawa before the J-League season kicked off this month. Lee also holds Japanese citizenship.
Urawa on Sunday said they were questioning an unspecified number of people who had displayed the banner, which also featured a Japanese flag, saying that their “words and deeds evoked discrimination.”
“Staff from a security guard company in the stands has reported that discriminatory remarks were heard during the match,” the statement said, without elaborating.
Urawa are managed by Austrian Mihailo Petrovic and have Brazilian Marcio Richardes as a midfielder, while Sagan’s manager and coach are both South Korean, as are several of the side’s players.
After his team’s 1-0 loss on Saturday, Urawa defender Tomoaki Makino tweeted that “this is not the way to treat players who fight for this team with pride.”
“Players and supporters cannot unite as one and produce results this way,” he wrote.
Urawa, the 2007 Asian champions who enjoy passionate backing from their large fan base, said the results of the probe would be released to the public.
“Discriminatory remarks and actions cannot be condoned,” they said.
J-League chairman Mitsuru Murai told Japanese media on Sunday that “we will deal with it in a stern manner” if the message was proven to be “discriminatory.”
The Japan Football Association had no immediate comment.
The incident comes as regional concern grows over an apparent right-ward shift in Japanese politics since hawkish Japanese Prime Minister Shinzo Abe swept to power in late 2012.
Tokyo is embroiled in diplomatic disputes with China and South Korea, with some of the animosity driven by Japan’s imperial aggression in the early 20th century.
The country’s often rocky relationship with Seoul was on display at the 2012 London Olympics when South Korea’s soccer team beat Japan in the bronze-medal match.
During the game, South Korean player Park Jong-woo waved a sign claiming that islands at the center of territorial dispute with Tokyo belonged to Seoul, earning him a two-match suspension.