As an anti-Islam video continued to spawn protests and violence around the region, Libya's prime minister said Thursday at least one person has been arrested -- and others were in authorities' sights -- tied to killings of a U.S. ambassador and three others this week.
"This is not acceptable to the Libyan people; this is not acceptable to our values," Prime Minister Mustafa Abushagur told CNN, referring to Tuesday's deadly assault on the U.S. consulate in Benghazi. "We are taking this very, very seriously."
The one suspect arrested and "three or four" being actively pursued are Libyans, Abushagur said, adding there are "suspicions that these people belong to some extremist group, but ... that is something we don't know."
The prime minister offered details on the case shortly after Libyan Deputy Interior Minister Wanis al-Sharif said that "some individuals" suspected in the case were in custody, according to state-run LANA news agency.
In response to the Benghazi attack, the United States deployed Marines to secure its interests in the region, as well as warships and drones to hunt for those responsible for killing the four American diplomatic staffers.
Killed in the attack in Benghazi were U.S. Ambassador Chris Stevens, two security officers and a State Department computer expert. U.S. officials Thursday identified the victims in addition to Stevens as security officers Glen Doherty and Tyrone Woods, and computer expert Sean Smith.
Posted in July on YouTube, it got more notice recently after Egyptian television aired segments and anti-Islam activists promoted it online. Numerous questions surround the film, which includes cartoonish scenes of Mohammed as a womanizer, child molester and ruthless killer.
The filmmaker had been identified since July 2011 by various names including Sam Bassiel, Sam Bassil and Sam Bacile. According to a joint statement from the U.S. Department of Homeland Security and the FBI, he had identified himself to news media as an Israeli -- a claim Israel's government denies -- and falsely claimed the movie was financed with help from over 100 Jewish donors.
Federal officials now say they believe his name is Nakoula Basseley Nakoula, who was convicted three years ago for bank fraud. A production staffer said he believed the filmmaker was a Coptic Christian who also went by the name Abenob Nakoula Bassely.
In addition to stressing there's no excuse for violence targeting U.S. diplomatic missions, U.S. Secretary of State Hillary Clinton has called the video "disgusting and reprehensible" and said it appears to aim "to denigrate a great religion and to provoke rage."
Here's the latest on the violence and unrest around the region, the response and the implications:
Since Tuesday's deadly assault in Libya -- and a protest the same day at the U.S. Embassy in Cairo -- small and large demonstrations have been reported in Israel, Gaza, Libya, Egypt, Yemen, Sudan, Tunisia, Morocco, Iraq, Iran and among Muslims in the Indian-controlled region of Kashmir. Security has been heightened at U.S. diplomatic missions worldwide.
While some protesters say they have not seen any of the online film, they were incensed by reports of its depiction of the Prophet Mohammed.
In the United States, the U.S. Department of Homeland Security and FBI has issued a joint intelligence bulletin urging state and local authorities, plus faith-based groups, to be on alert for anything "that could indicate pre-operational plotting against Jewish, Coptic, Islamic or any other faith-based communities; the filmmaker or promoters of the film; or retaliatory plotting targeting American Muslims and their places of worship."
Sen. Dianne Feinstein of California -- chairwoman of the U.S. Senate Intelligence Committee -- said there were 11 protests outside the United States on Thursday and more were expected in the coming days.
One of the largest protests Thursday and into Friday took place outside the U.S. Embassy in Cairo. One photo from Cairo shows a chalk drawing on the ground of a Jewish star with the words in Arabic, "Remember your black day 11 September." Demonstrators threw rocks and Molotov cocktails as police tried to disperse them by firing tear gas canisters.
At least 13 protesters and six police officers were injured, Egyptian government officials said.
The instability in Egypt is a primary concern to U.S. President Barack Obama, who warned in an interview with Telemundo that it would be "a real big problem" if the leaders in Egypt failed to protect American interests there.
Another massive protest took place Thursday in Sanaa, Yemen, where demonstrators breached a security wall at the U.S. Embassy as several thousand people protested outside.
Four protesters died during clashes with security forces outside the embassy, according to Yemeni security officials.
Twenty-four security force members were reported injured, as were 11 protesters, according to Yemen's Defense Ministry, security officials and eyewitnesses.
Here are details about other protests:
-- In Tunisia and Morocco, protesters massed in front of U.S. embassies.