T. Kumar, the Advocacy Director for Asia at Amnesty International, told reporters during a teleconference that there has been a significant erosion of human rights in China as the beginning of the games approaches.
"It is only three months until the Olympic Games begin in Beijing and China's human rights landscape remains as bleak as ever. In fact hosting the Olympic games has become a thinly veiled excuse to crackdown on freedom of expression and assembly," he said.
Kumar says a quarter of a million people have been arrested and held without charges or trial in labor camps during China's so-called patriotic re-education campaign.
"One of the primary concerns is the detention and imprisonment of human rights defenders," he added. "There are numerous reports that Chinese authorities have arrested and imprisoned activists. These are lawyers, journalists and other activists who are fighting to change human rights in China. This is on the rise."
Kumar points to the sentencing of prominent Chinese activist Hu Jia to three-and-one-half years in prison on subversion charges.
He has urged visitors coming to Beijing for the summer Olympics not to forget human rights abuses during the pageantry of the games.
Last month prior to the release of an Amnesty report on alleged rights abuses in the run up to the Olympic Games, China lashed out at the group.
Officials said any attempt by Amnesty to pressure Beijing over the Olympics would fail. A foreign ministry spokesman also accused Amnesty of being prejudiced against Beijing.
As part of its ongoing rights campaign, Amnesty has called on the U.S. Olympic Committee to grant the group access to athletes for briefings about the human rights situation in China.
"We are not against the Olympics," he explained. "We are not even advocating a boycott. What we want is, we want U.S. athletes to know which country they are going in and what type of human rights abuses are happening there."
Kumar also called on large U.S. corporations sponsoring the Olympics to speak out against human rights violations in China.
China has resisted linking human rights issues with the Olympics saying such accusations politicize the games.