Beijing-based activist Li Tingting, who works under the pseudonym Li Maizi, was taken from her home at about 11pm Friday night. Guangzhou-based Zheng Churan was also held in Guangzhou and both women's homes were searched.
Other feminist organizers planning demonstrations against sexual harassment on public transportation also disappeared over the weekend - such as Wei Tingting and Wang Man in Beijing and Wu Rongrong in Hangzhou.
Although most of the activists were released after Women's Day, Zheng, Li, Wei, Wang and Wu all remain in police custody.
This year, International Women's Day falls in the middle of the Two Sessions of the National People's Congress and Chinese People's Political Consultative Conference currently being held in the national capital. The government's need to "maintain social order" reaches fever pitch during the yearly ritual, during which any and all forms of popular political participation are quickly quashed.
Nevertheless, supporters have been shocked by the government's unsparing response to what they regarded as an uncontroversial and largely apolitical topic. "I thought sexual harassment on public transportation would be a really safe subject," one web user wrote online, "I never imagined this would happen, and that they still wouldn't be free over March 8."