In its run of 200 shows, the irreverent animated program “South Park” has mercilessly satirized Christianity, Buddhism, Scientology, the blind and disabled, gay people, Hollywood celebrities and politicians of all persuasions, weathering repeated protests and threats of boycotts. But last week, after an ominous warning from a radical Muslim website, the network that airs the program bleeped out all references to the Prophet Muhammad in the second part of a two-episode storyline that featured the holy figure dressed up like a bear.

In episode 201, which aired April 21, Comedy Central covered the character with a block that said “censored” and bleeped out audio apparently referring to Muhammad.

Many Muslims consider visual representations of Muhammad offensive.

The incident provides the latest example of how media conglomerates are still struggling to balance free speech with safety concerns and religious sensitivities, six years after Dutch filmmaker Theo van Gogh was shot to death for making a film critical of Islamic society.

Comedy Central declined to comment on the incident. But “South Park” creators Trey Parker and Matt Stone clearly disagreed with their bosses’ handling of the situation. A statement posted on their website said executives “made a determination to alter the episode” without their approval and noted that the usual wrap-up speech from one character didn’t mention Muhammad “but it got bleeped too.”

The network may have felt it had no choice after revolutionmuslim.com, the website of a fringe group, delivered a grim warning about the previous week’s episode, which seemed to depict Muhammad dressed as a bear. “We have to warn Matt and Trey that what they are doing is stupid and they will probably windup like Theo Van Gogh for airing this show,” the posting said. A photo of Van Gogh’s body lying in the street was included with the posting. “This is not a threat, but a warning of the reality of what will likely happen to them.”

Revolution Muslim, the extremist group that issued the graphic warning, is a relatively small fringe organization based out of New York, according to Oren Segal, director of the Anti-Defamation League’s Center on Extremism.

The organization, which formed in 2007 and includes about a dozen members, is mostly known for posting inflammatory and often threatening comments on its website, including a poem in October during Jewish High Holy Days asking God to kill all the Jews. Its members also stage protests in front of New York mosques, advocating a more fundamental form of Islam.

“This group definitely crosses the line, or is right on the line, in terms what is acceptable speech,” Segal said. “There is no direct link between this group and violence yet. But by posting this type of information, you never know who is going to take it seriously.”

Still, legal experts said the reaction by Comedy Central may set a dangerous precedent. UCLA law professor Eugene Volokh said that while he sympathizes with the predicament faced by the network, it has potentially empowered other extremists with its actions. “The consequence of this position is that the thugs win and people have more incentive to be thugs,” said Volokh, who teaches free speech and religious freedom law. “There are lots of people out there who would very much like to get certain kind of material removed, whether religious or political. The more they see others winning, the more they will be likely to do the same. Behavior that gets rewarded gets repeated.”