Singer Ashin Chen Hsin-hung of rock band Mayday performs on the stage at the Birds' Nest stadium on May 27, 2023 in Beijing, China.

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Tapei, Taiwan CNN  — 

China’s ongoing investigation into alleged lip-synching by a popular Taiwanese rock band may be linked to attempts by Beijing to influence the island’s upcoming election, Taiwan security officials have claimed.

Mayday, one of the most prominent rock groups in the Chinese-speaking world, has been under an official probe in China since early December over alleged lip-synching during their recent Shanghai shows. The band’s label has repeatedly denied the accusations.

In a recent briefing on security affairs, two Taiwanese intelligence officials claimed that Chinese authorities had for months pressured Mayday to publicly declare that both China and Taiwan belong to the same country. The repeated requests coincided with the start of the band’s China tour in May, claimed the Taiwanese officials, who asked not to be named for security reasons.

“They have been urged to declare their (political) stance during interactions with fans and public interviews,” the officials told the briefing, which was attended by CNN. The assessment was based on intelligence gathered by Taiwan’s security agencies in China, they added.

The Taiwanese officials claimed that when Mayday refused to comply, the Chinese Communist Party’s powerful propaganda department coordinated with state media to generate widespread public discussions about alleged lip-synching at their concerts to pressurize them.

“We have decided to publicize the incident because it is the first time they have gone after (Taiwanese artists) on such an unprecedented scale,” the officials said.

China dismissed Taiwan’s allegations as “ungrounded fake news”. Chen Binhua, a spokesperson for the State Council Taiwan Affairs Office, said Taiwan’s government was “intentionally fabricating rumors,” according to comments carried by the state-run Xinhua news agency on Thursday.

The Taiwanese officials said they suspected the Chinese investigation into Mayday could be related to Taiwan’s presidential election in January. Taiwan has previously accused Beijing of employing a range of disinformation, military and economic operations to influence the race.

Tensions across the Taiwan Strait have been on the rise in recent years, with China’s ruling Communist Party ramping up military and political pressure on Taiwan, where parties’ differing views on relations with China often make elections a litmus test for public sentiment on Beijing. Taiwan’s current ruling party is loathed by Beijing’s leaders.

CNN has been unable to independently verify Taiwan’s intelligence assessments.

But three sources familiar with Taiwan’s pop music scene said it is not uncommon for Taiwanese artists to face political restrictions in exchange for permission to perform in mainland China, a highly lucrative market because of its huge population.

CNN has reached out to the Chinese Communist Party’s Publicity Department for comment.

Rock Band Mayday arrives at the red carpet of the 28th Golden Melody Awards Ceremony on June 24, 2017 in Taipei, Taiwan of China.

The allegations

Some artists from Taiwan have encountered difficulties in China for being outspoken about the self-governing island, which China’s Communist Party leaders view as their own territory despite never having controlled it.

But Mayday – sometimes dubbed the “Asian Beatles” – has largely steered clear of politics and maintained huge popularity among mainland Chinese fans.

The lip-synching accusations centered on Mayday’s recent shows in Shanghai, where it performed eight times over 10 days in mid-November, to a combined audience of more than 360,000.

The controversy began in late November when a music vlogger on Bilibili, one of China’s biggest video-sharing platforms, posted a video in which he used computer software to analyze the vocals of 12 songs recorded live by a fan at Mayday’s concert in Shanghai on November 16.

The vlogger claimed his analysis