* ‘South Park’ showed Prophet Mohammad in bear suit

* Muslim group references slain filmmaker in ‘warning’

* New ‘South Park’ beeps out Mohammad’s name (Recasts with latest episode of show)

LOS ANGELES, April 21 (Reuters) - Satirical animated TV show “South Park” beeped out the words Prophet Muhammad and plastered its Wednesday episode with the word “CENSORED” after being issued a grim warning by a U.S. Muslim group.

The irreverent comedy show on Comedy Central also substituted a controversial image seen last week of the Prophet Muhammad in a bear outfit with one of Santa Claus in the same costume.

It was not immediately clear if the move was a bid to tread carefully following the warning against the “South Park” creators, or if they were poking fun at the fuss.

The little-known group RevolutionMuslim.com posted a message on its website earlier this week warning creators Matt Stone and Trey Parker “that what they are doing is stupid and they will probably wind up like Theo Van Gogh for airing this show.”

The website posted a graphic photo of Van Gogh, a Dutch filmmaker who was killed in 2004 by an Islamic militant over a movie he had made that accused Islam of condoning violence against women. It also posted a link to a news article with details of a mansion in Colorado that Parker and Stone apparently own.

Most Muslims consider any depiction of the founder of Islam as offensive.

The website warning followed the first in a two-part episode of “South Park” a week ago in which Prophet Mohammad was depicted in a bear outfit.

“South Park” has a history of biting satire against politicians, celebrities and the media. The two Colorado filmmakers are known to often work on “South Park” until just before they air, enabling them to react to current events.

In Wednesday’s new episode, Jesus Christ was depicted watching pornography and Buddha was portrayed snorting cocaine.

The head of Revolution Muslim, Younus Abdullah Muhammad, 30, defended the Web posting by his group.

“How is that a threat?,” he told Reuters earlier on Wednesday. “Showing a case study right there of what happened to another individual who conducted himself in a very similar manner? It’s just evidence.”

According to U.S. law enforcement officials, the federal government rarely prosecutes threat cases. The First Amendment of the U.S. Constitution gives broad protections to free speech, and what constitutes a threat is often subject to interpretation.

Muhammad described his group as an alternative media outlet with about 20 active posters to the website. He said the group “didn’t tell anyone to go to their houses and conduct violence” against Parker or Stone.

Comedy Central, a unit of Viacom Inc VIAb.N, has declined to comment on the controversy. (Additional reporting by Louis Charbonneau; editing by Jill Serjeant and Mohammad Zargham) (please visit our entertainment blog via www.reuters.com or on blogs.reuters.com/fanfare/)