Updated

The disqualification of a Taiwanese athlete at the Asian Games competition has set off a furor on this island of 23 million people, with media outlets and thousands of citizens accusing China of foul play.

The case of Yang Shu-chun underscores the fraught nature of relations across the 100-mile- (160-kilometer-) wide Taiwan Strait 2 1/2 years after Taiwanese President Ma Ying-jeou began a largely successful effort to lower tensions between the once-bitter rivals amid a welter of groundbreaking economic deals.

It comes just days after Ma warned Beijing that further Chinese efforts to undermine Taiwanese sovereignty could harm the reconciliation process. Ma was reacting to the demand of the Chinese delegation at an international film festival in Japan that Taiwan participate in the event under the name "China Taiwan" rather than the usual "Chinese Taipei," to make it appear the democratic island is under China's sway.

China and Taiwan split amid civil war in 1949. China insists the island is part of its territory despite its de facto independence.

Yang's disqualification occurred at the tail end of her match against Vietnamese competitor Thi Hau Vu, when judges ruled she was using an illegal sensor on the heel of her shoes.

Yang had an insurmountable lead at the time, and was seen as a serious threat to take gold. She broke down in tears when her disqualification was announced.

Games officials later upheld the decision against her, but the Taiwan delegation protested, insisting the sensors were carefully checked and approved before her match.

A post-match press conference deepened feelings of rancor, with Taiwanese and Chinese journalists trading barbs, including one from a Chinese reporter labeling the Taiwanese conduct as disgraceful.

Taiwanese perceptions of foul play in the Yang decision were fed by media reports that Zhao Lei, an Asian Games official from China, was one of its authors. The competition was eventually won by China's Wu Jingyu.

"Cheap moves by Chinese ... to get rid of Yang Shu-chun," the mass circulation Apple Daily trumpeted on its front page Thursday. "This is the most despicable scandal since taekwondo became an official Asian Games competition in 1984."

Netizens engaged in a fusillade of slurs against the Chinese, many calling them "pigs."

Not all Taiwanese jumped on the anti-China bandwagon. Two pro-government newspapers either downplayed the anti-China angle in their reporting or ignored it completely.

In the immediate wake of the incident, officials on both sides of the strait moved quickly to try to dampen popular anger.

Ma pointedly refrained from accusing Beijing of foul play, though he did call for Asian Games officials to reconsider Yang's case.

"The president demands the Asian Games committee conduct a thorough investigation on the incident and treat Taiwanese athletes fairly," presidential spokesman Lo Chih-chiang told the government-owned Central News Agency late Wednesday.

In China, Taiwan Affairs Office Director Wang Yi said he hoped the controversy would not undermine bilateral ties.

"Of course we want you to win more medals," he told Taiwanese reporters.

The Yang controversy erupted just 10 days before Taiwanese voters were set to go to the polls in municipal elections seen by many as a referendum on Ma's China-friendly policies.

Ma himself is up for re-election in early 2012, and a poor showing by his party in the municipal balloting could put him at a disadvantage against a still unnamed candidate from the pro-independence opposition.