TAIPEI - Police released 30 protesters, most of them students, Friday who were held after they broke into the education ministry in the capital Taipei to oppose "China-centric" changes to the school curriculum.
Increasing fears in Taiwan over Beijing's influence sparked a three-week occupation of parliament last year by student-led protesters opposing a trade pact with China.
Three journalists were also released.
All those arrested are facing charges of breaching government premises and causing damage.
Of the 33 detained in total, 22 have been released on bail and 11 who are under 18 are back in the care of their families.
The government condemned the overnight break-in, saying students had "crossed a red line".
Protesters scaled ladders to get into the building before barricading themselves in the education minister's office.
"They damaged the door of the minister's office, and used chairs and other things to lock themselves in the room," said senior police officer Lee Chuan-che.
"Police guarding the building tried to stop them from pushing their way in." Education minister Wu Se-hwa said charges against the journalists would be dropped if they had "purely engaged in reporting".
Television footage showed a protester being dragged across the floor inside the building by a police officer. Cable ties were used to secure protesters' hands behind their backs.
"Student groups who oppose the new curriculum guidelines have kept escalating their steps... despite the ministry's calls for rational discussion," the ministry said in a statement.
"What they did has crossed a red line." But student groups say their requests to meet with the education minister have been ignored.
A statement from the Liberty Times criticised the arrest of their photographer, saying he was prevented from doing his job and not allowed to contact his family.
"This harms news freedom and we strongly protest it," the newspaper said.
Talks break down
Around 100 police in riot gear guarded the ministry Friday and barbed wire was put up.
The protests came after talks broke down on Thursday evening with an education official over the proposed curriculum changes, which are due to be introduced across high schools in September.
Around 200 protesters had also rallied outside the ministry earlier in the week.
The students say changes to the high school curriculum undermine the island's sovereignty and have been introduced without proper consultation.
Taiwan split from China in 1949 after a civil war and is self-ruled, but Beijing still sees the island as part of its territory awaiting reunification - by force if necessary.
Relations have improved under current president Ma Ying-jeou of the Beijing-friendly Kuomintang party, leading to a number of trade deals but triggering growing public unease.
Curriculum changes disputed by protesters include a reference to Taiwan being "recovered by China" instead of "given to China" after the end of Japanese occupation in 1945.
The 50-year period of Japanese rule is also referred to as an era when "Japan occupied" the island, replacing the previous phrase "Japan governed".
The demonstrations have echoes of a mass campaign in semi-autonomous Hong Kong in 2012, which saw tens of thousands take to the streets against a bill to introduce mandatory Chinese patriotism classes into schools.