The Malaysian government has warned it could use tough anti-terrorism laws against bloggers who insult Islam or the country's king.
Raja Petra Kamarudin is the editor of a popular political website
The move comes as one of Malaysia's leading online commentators has been questioned by police following a complaint by the main governing party.
The new rules would allow a suspect to be detained indefinitely, without being charged or put on trial.
But officials insist the law is not intended to strangle internet freedom.
Deputy Prime Minister Najib Razak told The Straits Times that the move was aimed at getting some moderation in postings on the internet, especially on sensitive issues: "Some people feel that they have crossed the line, in making racist remarks," he said.
But the BBC's Jonathan Kent in Kuala Lumpur says the government also appears increasingly concerned about the growing online criticism of its record.
Raja Petra Kamarudin, the editor of one of Malaysia's most popular political websites, Malaysia Today, turned himself in to police on Wednesday, to answer allegations that he had mocked Islam and threatened racial harmony.
Raja Petra is known for his frequent criticism of Prime Minister Abdullah Ahmad Badawi and other government figures.
Bloggers who insult the king could be subject to anti-terror laws
"I was alleged to have insulted the king, and also Islam and incite racial hatred, so I am going in there to reply to all these charges. I promise I'm going to give them a hell of a tough time," he told the BBC before he turned himself in.
He defended his website, saying: "Many people, especially the non-Malays in this country, do not have a forum to air their views."
"We should not deny these people a chance to vent their feelings," he said.
Malaysia Today is believed to attract around a quarter of a million visitors a day, giving it more readers than most Malaysian newspapers.
The BBC's correspondent says that with a general election on the horizon, the government seems keen to send a signal to its online critics that it will only tolerate so much.