Video excerpts from an anti-Muslim movie provoked assaults by mobs on U.S. missions in Egypt and Libya. But there's little or no record of the man who says he directed and wrote it.

The man identified himself in a telephone interview with The Associated Press as Sam Bacile. He said he was an Israeli-born Jewish writer and the director of Innocence of Muslims. Bacile was the name used to publish excerpts of the movie online as early as July 2.

But his background came under growing doubt Wednesday. A Christian activist who said he was a consultant on the film told The Atlantic magazine "Bacile" is a pseudonym and that the man is neither Jewish nor Israeli. Israeli officials said there is no record of him being a citizen.

However, the news is unlikely to ease matters on the ground in the Middle East. Many Muslims find it offensive to depict the Prophet Muhammad in any fashion, much less in an insulting way.

This week's attacks on U.S. diplomatic outposts in Egypt and Libya, the latter of which claimed the lives of U.S. Ambassador Chris Stevens and three others on Tuesday, erupted after a 14-minute trailer of an obscure movie by a California real-estate developer. The film was posted on YouTube in English and later in Egyptian Arabic, but the video website has since made it unavailable in Egypt.

Initially, ultraconservative Islamists were suspected of being behind the attack in the eastern Libyan city of Benghazi. Advocating a strict interpretation of Islam, they have bulldozed Sufi shrines and mosques that house tombs in the Libyan capital, Tripoli, and other cities, including ancient sites dating back to 5,000 years ago.

A burnt car is parked at the U.S. Consulate in Benghazi, Libya, that was attacked and set on fire by gunmen, causing the death of the U.S. ambassador and three others. (Esam Al-Fetori/Reuters)

However, the U.S. government said Wednesday afternoon it was investigating the possibility the attack was orchestrated to mark the anniversary of the terror attack of Sept. 11, 2001, and used the street protests as cover.

And in New York, Libya's deputy UN ambassador blamed "an extremist group" for the attack in Benghazi that killed Stevens, whom he called "one of the greatest friends of Libya."

The movie trailer depicts Muhammad as a fraud, a womanizer and a madman in an overtly ridiculing way, showing him having sex and calling for massacres. An amateur cast performs a wooden dialogue of insults disguised as revelations about Muhammad, whose obedient followers are presented as a cadre of goons.

The film was being promoted by an extreme anti-Muslim Egyptian Christian campaigner in the United States.

Filmmaker calls Islam 'a cancer'

The man who gave the name Bacile claimed to be 56 years old and identified himself as an Israeli-American, though Israeli officials said Wednesday they had no record of him as a citizen.

The man purportedly went into hiding following the deadly protests, and has been conducting media interviews by phone from an undisclosed location.

"The U.S. lost a lot of money and a lot of people in wars in Iraq and Afghanistan, but we're fighting with ideas," he said. "Islam is a cancer, period."

The full two-hour film has been shown once, to a mostly empty theatre in Hollywood earlier this year, the man said.

Though he was apologetic about the American who was killed as a result of the outrage over his film, the purported filmmaker blamed lax embassy security and the perpetrators of the violence.

Memories of Rushdie book riots

A YouTube spokesperson said the website would not take down the trailer. The website's guidelines call for removing videos that include a threat of violence, but not those only expressing opinions. YouTube's practice is not to comment on specific videos.

It's not the first time the depiction of Muhammad has led to violence. The 2005 publication of 12 caricatures of Muhammad in a Danish newspaper triggered riots in many Muslim countries.

British author Salman Rushdie's 1988 novel Satanic Verses, which was inspired in part by the life of Muhammad, won kudos from critics in Britain, but prompted outrage among many Muslims, who considered it slanderous.

Deadly riots against the book erupted in Pakistan and India, and Iran's Ayatollah Ruhollah Khomeini issued a religious edict in 1989 calling for Rushdie's death.