SHANGHAI _ A blogger who sold stock tips to thousands of subscribers has been detained in northern China, as regulators try to reign in freelance operators amid a booming stock market.

Wang Xiujie, known to his readers as "Big Brother Leader 777" could face charges of running an unlicensed business and illegally raising funds, the official Xinhua News Agency reported Friday.

Starting in February, Wang sold subscriptions for tips sent by instant message, boasting his predictions had a 90 percent accuracy rate, Xinhua said.

It said Wang had been placed "under control" by the police's Internet investigations squad in the northeastern province of Jilin and officers were applying to formally arrest him. Police confirmed the detention on Wednesday, though it wasn't immediately clear when or where he had been taken.

Officers at the Jilin provincial police headquarters said no spokesmen were available to comment.

Wang's blog was last updated on July 1st. Its home page displayed a message from Wang thanking supporters and lashing out at "garbage" whom he accused of attacking him.

On a mini-resume posted beneath a picture of himself posing as super spy James Bond, Wang claimed that he had 17 years experience in the stock market. He described himself as a professional investor in stocks, bonds, postage stamps and antiques.

"Let's make a connection through stocks, let's make friends through stocks," the message said.

Stock tip gurus and informal fund managers have thrived as China's two stock markets more than doubled last year and surged a further 46 percent this year. The growth has attracted millions of small investors, many of them with only a hazy understanding of how the market works.

The government has registered its concern over operations such as Wang's, with the Public Security Ministry in late May designating "illegally recommending stocks" as a crime, focussing especially on operators distributing tips via the Internet.

The government earlier this month also announced stock advisers needed to gain permission from the securities regulatory commission.