It's something of a social networking mystery.
Why did Facebook block Kirk Cameron's upcoming faith-based movie, "Unstoppable"?
Cameron announced on his fan page Thursday that Facebook had blocked fans from posting any links to the website promoting his film because the content was labeled "abusive and unsafe."
"We have been officially shut down by Facebook and unable to get any response from them," Cameron wrote on his personal Facebook fan page. The film was made in partnership with Liberty University, the self-proclaimed largest Christian university in the world.
After Cameron alerted more than 500,000 Facebook fans of his predicament, the social networking site removed the block - without any explanation.
"This is a real victory," he said, thanking his fans and supporters for reaching out to Facebook. "If we work together, we really do have a voice."
"Unstoppable," which is expected in theaters in the fall, aims to answer questions about suffering and recounts the personal experience of a Cameron friend whose son battled cancer.
"I would understand if there was something truly unsafe about my stuff," Cameron told Fox News. "But I would encourage people to watch the trailer. Do you find anything offensive about faith, hope and love in the time of a tragedy?"
The film's website does not contain any graphic photographs, video or profanity.
However, Cameron said he received a message from Facebook telling him the website's content was labeled as "abuse" and "unsafe."
"This is my most personal film about faith, hope and love and about why God allows bad things to happen to good people," Cameron wrote. "What is 'abusive' or 'unsafe' about that?"
A Facebook media representative did not reply to an email seeking comment.
In recent months, the social networking website has come under criticism from conservatives and Christians who said their pages have been either blocked or banned because of "abusive" content.
Earlier this year, the "Chicks on the Right" Facebook page was shut down after they posted a message criticizing the White House. Facebook later apologized for that incident.