The "Crimes of Communism" conference has opened in Prague to look at communism's legacy, ask how to hold rights violators accountable, and consider communist regimes still in existence.

The keynote speaker, Harry Wu, who spent nearly 20 years in the Chinese system of forced labor camps, or laogai, served as a reminder that in some parts of the world, communism is not a thing of the past.

"Communism is a crime. But today you have a conference to talk about it, and that's great," Wu said. "We have to clean it up. But the communists are still running things inside China. We cannot forget that."

After his release in 1979, Wu immigrated to the United States, where he founded the Laogai Research Foundation to study human rights abuses in China.

He added that while the West engages China economically, it must not ignore the repressive nature of its communist regime.  (Read more from Radio Free Europe)