A flood of posts allegedly from Chinese mainland Internet users on Wednesday inundated Taiwan opposition leader Tsai Ing-wen's Facebook page, with many attacking her party's pro-Taiwan independence position and demanding the island be united with the mainland.

As of Wednesday night, more than 90,000 messages had been posted under a Facebook post Tsai wrote on Tuesday, as Internet users from both sides fiercely traded accusations.

Tsai is the chairwoman of Taiwan's main opposition, the Democratic Progressive Party (DPP), and a front runner in the upcoming "presidential" election.

The surge in posts, which started late Tuesday night or early Wednesday morning, surprised many, as Facebook is blocked on the mainland.

"The incident shows the mainlanders' long-standing discontent with Tsai's political stance," Chang Ya-chung, an international relations professor at National Taiwan University, told the Global Times.

New chapter

The incident comes after President Xi Jinping's landmark handshake with Taiwan leader Ma Ying-jeou in the first meeting between the leaders of the two sides since 1949 in Singapore on Saturday. The meeting has opened up a whole new chapter in cross-Straits relations.

According to Chang, recent negative remarks on social media by Tsai over Ma's meeting with Xi might be the trigger for the online spat.

Tsai had said in an earlier Facebook post that Ma's performance at the Xi-Ma meeting in Singapore had angered many people in Taiwan, and that what Ma said deviates from Taiwan's status quo, which could not represent mainstream public opinion in Taiwan.

'Welcome to Facebook'

The initial article made by Tsai on Facebook was innocuous, but when Tsai noticed the numerous comments, she replied in a separate post, saying "Welcome to Facebook."

Up to late Wednesday, the latter had garnered around 90,000 likes and was shared by more than 4,500 Facebook users.

It has not yet been confirmed that the posts, many written in simplified Chinese, are from the mainland. However, DPP spokesperson Cheng Yu-peng said they seemed genuine and did not appear to be machine-generated spam, Reuters reported Wednesday.

"One thing is clear - Tsai will benefit from the incident. It consolidates Tsai's political status and offer her a chance to reiterate her political stance," Chang said.

This is not the first time that mainland Internet users have flooded political figures' social networks, many of which are blocked in China.

In February 2012, many mainland Internet users "occupied" President Obama's Google+ page, in a tongue-in-cheek reference to the Occupy Wall Street campaign, the BBC reported.

"Thanks to globalization and Internet development, more and more mainland people want to be heard by the world and interact with people from other regions and countries," He Hui, director of the Public Relations and Public Opinion Institute of the Communication University of China, told the Global Times on Wednesday.

According to He, this incident shows that many mainland Internet users are eager to participate in politics and express their opinions.

"They want to show their patriotism and their opinions on cross-Straits issues," He noted.

"Everybody has the freedom to express their opinions. This incident won't affect cross-Straits relations," Lü Cuncheng, a political science researcher, told the Global Times.

The derogatory comments came only from a few users, and friendly relations and cooperation are still the mainstream for both sides, said Lü.

"This is just an isolated incident. The majority on both sides has a clear understanding of the relationship between the mainland and Taiwan, and it won't be affected by some comments," he added.