UPDATE: Here is a statement from Matt and Trey:

“In the 14 years we’ve been doing South Park we have never done a show that we couldn’t stand behind. We delivered our version of the show to Comedy Central and they made a determination to alter the episode. It wasn’t some meta-joke on our part. Comedy Central added the bleeps. In fact, Kyle’s customary final speech was about intimidation and fear. It didn’t mention Muhammad at all but it got bleeped too. We’ll be back next week with a whole new show about something completely different and we’ll see what happens to it.”

PREVIOUS: South Park creators defied death threats from a radical Muslim group by continuing their Prophet Muhammad-themed storyline. But the network, wisely, took precaution by censoring Muhammad’s image and name. It’s not clear if that would appease the New York-based group Revolution Muslim, which posted a message on its website after last week’s 200th episode claiming that producers Trey Parker and Matt Stone had insulted their prophet by briefly showing him in a bear costume (any physical representation of the prophet is considered blasphemous by Islam) and threatening that they will “probably wind up like [Dutch filmmaker] Theo Van Gogh” who was murdered by Muslim extremists. Last night, the Muhammad character’s face was covered by a black box and the mention of his name was bleeped.

Comedy Central did confirm that they asked Parker and Stone not to show Prophet Muhammad and that they added additional bleeps in the episode after it was delivered. The network wouldn’t comment whether security for Parker and Stone had been beefed up in light of the threats, or whether last night’s episode will ever be repeated. As of now, it’s still not available online.

Parker and Stone have built a brand of crossing all kinds of lines and being equal offenders to celebrities, politicians and religious leaders. But the Muhammad incident does raise the question about the limits of artistic freedom and free speech when it comes to religious content and simple self-preservation. Did they go too far?