In scenes unprecedented even for Taiwan's famously rowdy legislature, hundreds of students and activists have occupied Parliament over a controversial service trade pact with China that many fear will harm local jobs and small businesses.
Thousands more rallied outside to protest against what they call "black box politics" after the ruling party rammed through an initial review of the accord.
Their action further complicates ratification of the long-delayed pact aimed at opening up service sectors on both sides, as the protesters vow to stay on until Friday, when the legislature is supposed to sit for the Bill's second reading.
On Tuesday night, the protesters stormed the chamber and barricaded themselves inside with chairs after scuffles with police.
Hoisting banners in front of Taiwan's founding father Sun Yat-sen's portrait, they said they were taking up the cudgels against the "illegal" move by President Ma Ying-jeou's Kuomintang (KMT) to "sneak" through the review approval, reneging on a promise to conduct a clause-by-clause examination of the pact.
This came after brawls erupted in Parliament on Monday, when KMT legislators insisted the review had been automatically approved at the end of a three-month period, marked by stalling tactics of the opposition Democratic Progressive Party (DPP).
The pact aims to open up more than 100 service sectors to allow investors on both sides to move into areas from financial and transport to entertainment and tourism.
It was signed by Beijing and Taipei last June but has yet to be ratified by Taiwan's legislature.
While Beijing views it as granting favourable terms to Taipei in a process aimed at lubricating economic integration, Taiwan's small and medium-sized enterprises from hair salons to travel agencies fear Chinese competition.
Others worry it will further increase Taiwan's reliance on China - and strengthen Beijing's influence in local politics.
Meanwhile, the yet-to-be-ratified pact remains a sticking point in a relationship that Beijing and Mr Ma are seeking to improve. Mr Ma warns that any further delay would damage Taiwan's standing as it seeks to negotiate free trade pacts with other economies.
The DPP's Frank Hsieh, a former premier, told The Straits Times the stalemate can be resolved if the KMT "returns to the original starting point of reviewing the clauses line by line".
The veteran politician added that the DPP is proposing a few amendments, and "if KMT can come to terms with these, and return to the original status, we can come to a consensus".
But KMT legislator Wu Yu-sheng, denouncing the protesters' actions as those of a "violent mob undermining Taiwan's democracy", insisted the ruling party "will not give in" to the demands.
Additional reporting by Brenda Wu in Taipei.
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