TAIPEI, Taiwan — President Tsai Ing-wen sat on the stage answering young people’s questions, from climate change and the minimum wage to how to better represent Taiwan’s indigenous communities in the school curriculum.

Behind the scenes at the live-streamed candidate forum last month, an army of fact-checkers was huddled around computers, assessing her every word. Alarms rang on their screens when viewers queried something said by Tsai, who is seeking reelection Saturday.

Then Josh Wang, from the ­Watchout civic group, stepped up to the microphone. “We’ve been fact-checking you as you spoke,” he said, “and we’ve found three problems.”

Tsai, of the independence­leaning Democratic Progressive Party, smiled, then reiterated two points and clarified a third.

The next night, Watchout’s crew scrutinized Han Kuo-yu, the candidate for the China-friendly Kuomintang, and found five areas of concern. The conservative Han, who is mayor of Kaohsiung, conceded that he had overstated the investment he had attracted to the city by a factor of 100.

Watchout, which began as a congressional watchdog but has morphed into a crowdsourced cohort of fact-checkers, is one of the grass-roots groups tackling disinformation ahead of Saturday’s vote. These groups say they are acting as “fake news detergent” to scrub away the lies in Taiwan’s raucous political and media landscape.

Fake news and disinformation campaigns have become major concerns in Western democracies, notably including Russia’s interference in the 2016 U.S. election. But analysts say they pale in comparison to China’s efforts to sow discord in Taiwan, a self-ruled island that Beijing has vowed to bring under its control.

“China’s influence has penetrated into every corner of this country,” said Wu Jieh-min, a sociologist at Academia Sinica, Taiwan’s national academy. “Politics, the economy, society, culture and religion.”

Taiwan is subjected to more foreign disinformation from China and other governments than any other place, V-Dem, a research institute of Sweden’s University of Gothenburg, found in a study. “By circulating misleading information on social media and investing in Taiwanese media outlets, China seeks to interfere in Taiwan’s domestic politics and to engineer a complete unification,” the report said.

A man claiming to be a Chinese operative and who is now seeking political asylum in Australia said he had been sent to interfere in Taiwan’s elections. While there is skepticism about Wang Liqiang’s claims, some also ring true.

A web of deception

China has a record of meddling in Taiwan, which it views as a breakaway province, and has stepped up disinformation efforts in recent years.

The objective is not only to undermine Tsai, who has a strong lead in opinion polls and whose reelection would entrench generational antipathy toward the mainland. Beijing also aims to sow division and political chaos and thereby undermine the ­democratic institutions that ­distinguish Taiwan from the ­Communist-run mainland.

The fruits of those efforts could materialize in Taiwan’s parliament, the Legislative Yuan, which Tsai’s DPP controls. Party operatives say they are worried about a repeat of local elections in 2018, when the Kuomintang won in a landslide.

That victory was partly due to China’s deluging Taiwan with fake news favorable to the mainland and aggressively promoting that content, said Puma Shen, a professor who runs DoubleThink Labs, which monitors the flow of disinformation. “They have content farms that post articles to fan pages to make sure it’s disseminated on Facebook and lots of people see it,” Shen said, adding that many Taiwanese who share the stories did not know they were created by China.

This time, Shen said, Chinese operatives have adopted a more sophisticated approach, targeting specific voter groups. “I think that’s more clever for them because if you want to affect the election, then you only need to target, like, 10 or maybe 12 percent of people in Taiwan,” he said.

Fake news stories are particularly rampant on Line, a messaging app where news is often shared in private groups with hundreds of members.

Stories that have gone viral include rumors about Tsai, including one that is the Taiwanese equivalent of birtherism: that she does not have a PhD. The London School of Economics has confirmed that Tsai completed and was awarded her doctorate in law in 1984.

Other false reports have contended that the Tsai administration will retroactively take back people’s pensions, and that Joshua Wong, the Hong Kong democracy activist, kicked an old man during a visit to Taiwan.

Facebook has removed scores of pages and groups that violate its standards, most backing the Kuomintang’s Han, and has set up a round-the-clock “war room” in Taiwan. Google and Line are also trying to root out disinformation.

But traditional media outlets are also ripe for exploitation. “Observers report many examples of Chinese disinformation campaigns. For instance, China provides funds to media that adopt a more pro-Beijing line in their reports,” the Swedish report said.

Taiwan has more than 100 TV stations, all hungry for content. There is relatively little checking, local analysts say, which leads to a social media-like atmosphere even in traditional news sources.

Scrutiny is particularly falling on the CTiTV cable channel and China Times newspaper, which are owned by the Want Want Group and are viewed as mouthpieces for China’s Communist Party. After the Financial Times published a story quoting journalists at the two outlets describing how Beijing influences coverage, Want Want said it would sue the paper. China Times president Wang Feng said the report was premised on a “baseless accusation.”

Tsai’s government has accused some local media outlets of working with Beijing to spread its propaganda. Her administration recently passed an anti-infiltration measure designed to counteract China’s influence. The legislation, criticized by the Kuomintang, bans “hostile” foreign forces from campaigning and lobbying, funding political candidates or the media, and otherwise trying to interfere with Taiwan’s political and social order.

“Democracies around the world are working to prevent infiltration from China, & today #Taiwan joined in this effort by passing an anti-infiltration act to defend our democracy,” Tsai tweeted last month.

Asked to respond to allegations that China is interfering in Taiwan’s elections, Ma Xiaoguang, director of the information bureau of Beijing’s Taiwan Affairs Office, said such charges were plucked “completely out of thin air and have ulterior motives.”

“We have always stayed out of elections in Taiwan, and resolutely oppose any actions and words that frame and smear the mainland,” he said in a faxed response.

Following the money

One problem for those trying to counter China’s influence is producing incontrovertible evidence that the Communist Party is behind these efforts.

“It’s really difficult to track the origin of this funding, to find a smoking gun,” said Ketty Chen, vice president of the Taiwan Foundation for Democracy think tank. The money trail is obscured by shell companies, business interests and public relations firms, she said.

For now, authorities and civil society groups are trying to raise awareness and counteract disinformation. After the local elections in 2018, Tsai’s government set up fake-news task forces that aimed to shoot down false assertions within two hours of their appearance.

“I think the government learned a lesson,” said Joseph Wu, Taiwan’s foreign minister. “We need to come out in a very speedy way to clarify what is the true information. And we’ve been doing that throughout the last year and it seemed to have a fair effect.”

There is also a generational aspect. “Young people are becoming more and aware that information is being manipulated,” said Sasha Chang, a YouTube channel host who has interviewed the major candidates. “There are a lot of conspiracy theories, making people feel more and more worried.”

To spread the word among older voters, who tend to be more supportive of the Kuomintang, young people have been visiting community centers and hiking trails to explain fake news and to help senior citizens add fact-checking bots to their Line chat groups.

Those working to counteract Chinese influence voice optimism that truth will prevail. “I’m positive about the resilience of Taiwanese democracy,” said Chen. “Taiwan is a young democracy, only 30 years old, but our civic organizations are very vibrant.”

Alicia Ying-yu Chen contributed to this report.