Chinese-American Commentator and Investor Is Arrested in Beijing SHANGHAI - A prominent investor and online social commentator was detained Friday in Beijing on charges of soliciting prostitution just after the government stepped up a campaign aimed at cracking down on online activism. The investor, Charles Xue, 60, was picked up Friday evening with a 22-year-old woman, the police said in a statement. Mr. Xue has been known in China for his investments in Internet and technology companies, including the telecom company UTStarcom. But in recent years, he also became an Internet celebrity for his investing tips and commentary on social issues, including child trafficking and the plight of the underprivileged. He has attracted more than 12 million followers to his account on Sina.com's Weibo service, a popular microblog platform similar to Twitter. The government has been cracking down on social media activists who have exposed corruption or stirred up interest in social issues. Some prominent activists have been detained, including a journalist and people working at public relations firms. Whether this is the case for Mr. Xue, who is also known as Xue Manzi, is unclear. But people posting on microblogs on Sunday speculated that the arrest was a setup and an attempt to stifle online commentary. Mr. Xue, who grew up in China but is a naturalized American citizen, could not be reached for comment on Sunday. Because microblogs have grown into a powerful social force that has led to the downfall of some prominent government officials, analysts say the authorities are determined to put stricter controls in place and have pressed Internet companies to censor more content.