BEIJING — One of five leading Chinese feminist advocates said she went through lengthy and verbally abusive interrogations after she was conditionally released in a case that has attracted international attention. Wu Rongrong, a 30-year-old advocate for women’s rights, said in a statement Saturday that she endured an eight-hour police interrogation in a hotel room in the eastern city of Hangzhou. Wu and four others were detained last month, just ahead of International Women’s Day, as they were planning to hand out stickers and flyers against sexual harassment in several Chinese cities. Foreign governments, rights groups and luminaries including U.S.