The family of the producer of "Innocence of Muslims" joined him in hiding as more cast members of the film that outraged the Islamic world insisted they had been duped into making it.
Nakoula Basseley Nakoula, a 55-year-old Egyptian Copt and fraudster who was sentenced to 21 months in prison in June 2010, has not been seen since Saturday when he was questioned by his parole officer.
Before dawn on Monday, officers from the Los Angeles County sheriff's department escorted four members of Nakoula's family out of their home to be driven in unmarked police vehicles to an undisclosed location to join him.
The risks now facing those involved in the production of the film, which depicts the Prophet Mohammed as a thuggish womanizer, were underlined when more threats emerged from the Middle East.
In Lebanon, Hezbollah leader Hassan Nasrallah warned that the United States and the whole world would feel "dangerous repercussions" from what he called the "worst attack ever on Islam."
And in Egypt, according to the SITE terror monitoring group, Salafist preacher Ahmad Fouad Ashoush issued a fatwa, or religious ruling, calling on all Muslims to seek the death of the cast and crew of the film.
Nakoula's family concealed their faces as they left their home in the Los Angeles suburb of Cerritos. Local website Patch, in its Cerritos edition, identified the four as Nakoula's wife, his two sons and a daughter.
"They decided they would be safer where they could move about and live a normal life," said Steve Whitmore, a spokesman for the sheriff's department, quoted by ABC News.
"All we did was pick them up and reunite them with Mr Nakoula.... What they told me is that for the time now and for the immediate future, for the weeks and months to come, they will not be returning to this address."
Nakoula had been convicted of aggravated identity theft in connection with a check kiting scheme that, according to prosecutors, used false names and Social Security numbers.
He spent about a year in prison before his release on parole. Speculation in US news media on Monday focused on whether his involvement with the film might have violated his terms of parole.
Protests over a YouTube trailer for the anti-Islam film erupted last Tuesday in Egypt as well as in Libya where an armed mob attacked the US consulate in Benghazi and killed US ambassador Chris Stevens and three other Americans.
The demonstrations, sometimes violent, later spread to other Muslim-majority nations in North Africa, the Middle East, Africa and Asia.
Two more American actors emerged Monday to discuss the making of the film, saying its anti-Islamic intentions had been concealed from the cast and crew when shooting was under way.
Lily Dionne told CNN she signed on to the project -- originally titled "Desert Warrior" with a central character named George -- in response to a casting notice on the Craigslist website.
Dionne, who had just arrived in Hollywood to pursue her acting career, said Nakoula appeared on set to be in total control of the project, to the point of arguing with the director at times.
"He had a vision... he wanted things a certain way," she said. "He knew what he was doing. He was playing us all along."
Of the plot, she said: "We did wonder what it was about. They kept saying 'George.' Like, this was the Middle East two thousand years ago. Who's 'George'?"
Later, when the project was in post-production, Dionne and other cast members were called in to record "specific words, like Mohammed, for example. It was isolated. It wasn't in context."
Another actress, Anna Gurji, told how she had auditioned last year for a supporting role in what she called "an indie low-budget feature movie ... about a comet falling into a desert and ancient tribes fighting over it..."
"A year later, the movie was dubbed (without the actors' permission), the lines were changed drastically and the movie was morphed into an anti-Islam film," she said.
"Even the names of the characters were changed. And the character I had scenes with, GEORGE, became MUHAMMAD," she added, in a letter to British writer Neil Gaiman, who posted it on his blog (journal.neilgaiman.com).