China claims democratic Taiwan is part of its territory and has threatened to use force to take it, while Taipei accuses Beijing of using espionage and infiltration to weaken its defences.

Taiwan's National Security Bureau (NSB) introduced the platform Sunday with a one-minute AI-generated video showing a Chinese civil servant witnessing colleagues being removed and investigated, "reflecting a pervasive atmosphere that everyone is on edge under China's totalitarian regime", it said in a statement.

The website invited Chinese nationals "who share the same values of democracy" to collaborate on reporting on Beijing.

An "increasing number" of people have approached agencies in Taiwan "wishing to provide various types of information", the NSB said.

"There really are a lot of dissatisfied people inside China, whether among ordinary citizens, or within the government or the military," said Su Tzu-yun, a military expert at the Taipei-based Institute for National Defense and Security Research, adding that the platform would make sources of intelligence more "diverse".

"Because of (Chinese President) Xi Jinping's one-man dictatorship, there's significant discontent... I think this initiative does have potential," he said.

The NSB said it would "rigorously filter", evaluate and follow up on submissions to the platform.

- A 'bull's-eye' -

On Monday, the bureau told AFP that the website had been working "normally" in its first day of operations, but provided no further information.

"What mainland China now sees is a website that is so clearly there in the open," said Chieh Chung, adjunct assistant professor from Tamkang University, adding the reporting platform carried "significant risk" for Taiwan.

"Even if you have all kinds of measures, it becomes a bull's-eye."

The NSB said the reporting channel was based on "practices adopted by intelligence agencies in the United States, the United Kingdom, and Israel".

These countries have a "great deal of money and manpower" to filter information and strengthen cyber security, Chieh said.

But Taiwan's situation "is exactly the opposite," he said, adding that mainland China "devotes more talent than we do, and its cyber-attack capability is constantly on the rise".

"I'm quite worried about whether we have the resources to fight this battle," he said.