China has denied media reports that its investigation into alleged lip syncing by a popular Taiwanese rock band is politically motivated.
The reports alleged that Beijing asked Mayday to make pro-China comments and that when the band refused, the inquiry was started to put pressure on them.
Beijing's Taiwan Affairs Office has dismissed the reports as "fake news" and a "complete fabrication".
Taiwan says it is looking into the claims.
Mayday, known for their "positive rock music", are among the most successful Taiwanese acts in mainland China.
China's National Radio and Television Administration asked Mayday to publicly declare its support for Beijing's position that self-ruled Taiwan is part of China, Reuters news agency reported on Thursday, citing an internal Taiwan security note.
China sees Taiwan as a breakaway province that will eventually be under Beijing's control, while Taiwan sees itself as distinct from the Chinese mainland, with its own constitution and democratically elected leaders.
Reports alleged that Beijing wanted to use Mayday to sway voters, particularly the youth, ahead of Taiwan's presidential and legislative elections on 13 January.
The requests for Mayday to issue statements in Beijing's favour went on for a few months and reportedly coincided with the start of the band's tour of China in May, CNN reported, citing a recent briefing on Taiwan's security affairs.
Officials at the security briefing said that when Mayday did not agree to the requests, Chinese authorities co-ordinated with state media to stir up discussion of Mayday's alleged lip-syncing and threatened the band with a penalty.
Commercial regulations in China prohibit lip syncing before paying audiences because it is "deceptive". The offence is punishable by a fine of 100,000 yuan ($14,110, £11,240). Artists can also be banned from performing and their show organisers could have their licences revoked.
However, the ban is rarely enforced and lip syncing is not uncommon for performers in China. This led some Chinese social media users to question why Mayday appeared to have been singled out when many performers, even those who appear on state television, are believed to lip sync.
Taiwan's Mainland Affairs Council said it was investigating the allegations and that if they were true, they would worsen "negative impressions" of the Chinese Communist regime among Taiwanese youth.
Taiwan's main political parties criticised Chinese authorities for alleged political interference.
Opposition party Kuomintang said it "strongly condemns such actions" if the allegations were true.
"Not only will fans reject such interference, but it will also seriously harm the feelings of people in Taiwan and does nothing to enhance cross-strait exchanges," said its spokesman Wang Min-shu.
The reports show that China will "stop at nothing to intervene in [Taiwan's] election", said the ruling Democratic Progressive Party.
Beijing's Taiwan Affairs Office condemned the accusations as a deliberate move by Taiwanese authorities to "create rumours".
"This is insidious and malicious political manipulation. I hope our Taiwan compatriots will recognise their schemes and will not be deceived," said Chen Binhua, a spokesman for the office.
The investigation against Mayday was made public in early December. The band and its music label have denied that they lip synced, but had said they are co-operating with Chinese authorities.
China has been ramping up military and political pressure ahead of Taiwan's pivotal presidential race, such as by sending a record number of military planes near the island.
