Meanwhile, China Central Television (CCTV) premiered a dubbed version of the first season of US drama "Game of Thrones" on one of its paid cable channels on Sunday, a series that is widely considered more obscene and violent than the four banned shows.

Other popular American TV series, such as "The Walking Dead," "House of Cards" and "Vampire Diaries," are also still available online.

Li's confusion was shared among the country's netizens, with many criticizing the move.

"The 'policy' is too unpredictable; I'm wondering if we will be prohibited from watching any western shows," a user nicknamed "Zhen Zhici" complained on Chinese microblog site Weibo.

Another netizen nicknamed "Elsa" said, "Why was 'Big Bang' pulled off? It is far outweighed in nudity and erotic scenes by 'The Game of Thrones' while not at all as terrifying compared with 'The Walking Dead.'"

There were also supportive voices online, as some thought the move may help purify China's cyber space, where is glutted with rampant inappropriate content and leave some space for the nurturing and growth of locally made series.

Yin Hong, a film and television professor from Tsinghua University, said he was surprised for the withdrawal, but he had heard of no such move as tightened censorship on imported series.

There should be more transparency and relevant authorities should respond to the public concerns, according to Yin.

More foreign shows may be taken off video sites

China exports rights to TV show for first time	Chinese mainland stars who have won at the HKFA