Wu was being investigated over accusations made online of “tricking young girls into having sex with him,” according to a statement by police in the Chaoyang district of the Chinese capital Beijing late on Saturday.
Wu has previously denied the accusation and was not immediately contactable on Sunday.
Wu’s studio did not immediately respond to a request for comment. His law firm did not answer calls. The Canadian embassy in Beijing did not immediately respond to an e-mailed request for comment.
It was not immediately clear whether Wu’s arrest was linked to the student who made the accusations in July.
Wu made his Hollywood debut in the 2017 sci-fi film “XXX: Return of Xander Cage” and was previously a member of K-pop group EXO.
At least a dozen brands including Porsche and Bvlgari had cut ties with Wu after the accusation, which have caused a social media storm in China.
Chinese state media have indicated that Wu’s celebrity status and foreign citizenship are unlikely to help his case.