Authorities in the southern Chinese province of Guangzhou have prevented a prominent women's rights activist from leaving the country after she planned to attend a forum in Thailand. The activist, who asked to be identified only by her surname Zheng, said she had been stopped from boarding a flight to Bangkok on Thursday 13th November by China's border guards. "I was refused permission to leave the country," said Zheng, who had planned to take part in the U.N.-sponsored Asia-Pacific NGO Forum on Friday. "They took me into a glass-walled room and they confiscated my cell phone and my travel documents without giving any reason whatsoever," she said. "Then they told me to wait." Zheng was traveling with a fellow activist surnamed Liang. Border guards also confiscated her phone and shut her up in the same room. "There was a female border guard watching over us, and we waited for a very long time," Zheng said. "I asked to go to the toilet but they just said 'wait a minute.'" "I waited there for three hours, but they didn't let me go to the toilet." 'Under investigation' She said the authorities had initially suspected "a problem" with Liang's documents, but eventually let her go after "checking them out." "I was taken into an interview room with a male border guard ... who told me I had been refused permission to leave the country," Zheng said. "I asked him why, and he said that I am under investigation, so I can't leave." She said the border guard refused to provide a written document confirming the reason he had given her. "He said he didn't have the authority to issue such a document," said Zheng, who was still at the airport waiting for her luggage to be returned to her when she spoke to RFA. "He wouldn't say who was supposed to be investigating me; he just said it was the 'relevant departments,'" she said. A different reality China's ruling Communist Party has promoted gender equality, at least in theory, since it came to power in 1949. But women's and rights campaigners say the reality is very different on the ground, and that discrimination still presents major obstacles to equality. The Bangkok forum is part of a series of U.N.-backed events promoting the rights of women and girls in the wake of the Fourth World Conference on Women in 1995. The conference, hosted in Beijing, set out a challenging program of improvements to the rights and opportunities offered to women and girls around the world, as well as requiring governments to report back to the U.N. on progress in key areas. The Beijing Declaration produced by the conference included a pledge to "ensure equal enjoyment of all human rights and fundamental freedoms for all women and girls." It also called on governments to "develop the fullest potential of girls and women of all ages, ensure their full and equal participation in building a better world for all and enhance their role in the development process." Discrimination widespread Zheng has been a vocal protester against discrimination against women in state and corporate hiring practices in China, leading a movement in Guangzhou in which activists shaved their heads in protest over sexist job advertisements. Some of these included different entry requirements for men and women to top-level university courses and jobs. Chinese rights groups say that 70-90 percent of female graduates have experienced some form of discrimination against women during their search for work. Activists say that Chinese women face major barriers to finding work in the graduate labor market and fear getting pregnant if they have a job, out of concern their employer will fire them, a common practice despite protections on paper offered by China's Labor Law. Overseas rights groups cite high levels of unemployment among highly qualified Chinese women, while unskilled migrant women workers are preferred by employers as being less likely to take a stand on labor rights, pay, and working conditions.