Prime Minister Hesham Kandil said "a number" of those involved in the tense, sometimes violent protests, which began Tuesday, later confessed to getting paid to participate, according to the state-run Middle East News Agency. He noted, too, that some of the demonstrators were acting on their own and weren't paid to vent their anger against the United States over an inflammatory anti-Islam film that was privately produced in that country.
Kandil did not say whether the government knew or suspected who paid the demonstrators, according to the MENA report.
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Also Saturday, some semblance of normalcy finally returned to Cairo after riot police successfully pushed away demonstrators from the U.S. diplomatic as well as nearby Tahrir Square.
This action gave crews the opportunity, finally, to clear debris-strewn streets, local businesses to assess damages and traffic to begin crawling back to normal.
Saturday's protests in the Egyptian capital were mostly peaceful, though scores of people were nonetheless arrested and injured in clashes. One death was reported, but government officials later said it was unrelated to the demonstrations.
Muslims have been livid over a 14-minute trailer for "Innocence of Muslims," an obscure film that mocks the Prophet Mohammed as a womanizer, child molester and ruthless killer.
Two months after the film's trailer was posted online on YouTube, and days after it got attention in Egyptian media, Cairo residents first expressed their ire Tuesday, the 11th anniversary of the September 11, 2001, attacks, with protests targeting the American embassy.
Outpourings soon spread like wildfire across the Muslim world. As a result, Western diplomats found themselves and their missions under siege.
The region has been on edge after those initial volatile Cairo protests and the killings of U.S. Ambassador to Libya Chris Stevens and three other American officials at the U.S. consulate in the Libyan city of Benghazi.
Relations between the United States and Egypt have cooled since the overthrow last year of ousted President Hosni Mubarak and the election of President Mohamed Morsy, the country's first democratically elected leader. Before he became president, he was a leader in the political arm of the Muslim Brotherhood, the popular Islamist movement.
When protests in Cairo began Tuesday, police and Egyptian troops formed defensive lines around the embassy to stop demonstrators from advancing. But they did not prevent protesters from scaling the embassy fence and placing a black flag atop a ladder in the American compound.
Police arrested a handful of protesters at the time, but the failure of Egyptian authorities to take action sooner has been widely questioned, as has initial response from Morsy.
Morsy initially focused his criticism on the anti-Muslim film as an unacceptable slap at Islam. But after speaking with U.S. President Barack Obama, Morsy on Thursday directly criticized the violence.
"Those who are attacking the embassies do not represent any of us," he said from Brussels, Belgium, where he was visiting the headquarters of the European Union.
Discussing Egypt's relationship with the United States, the prime minister, Kandil, said Egyptian officials believe that Washington is "sincere" in wanting to foster "good relations," adding that Egypt's chief goal is to create "balanced relations," the MENA report said.
"Relations between countries of the so-called Arab Spring and the West have not yet taken complete shape," Kandil said, stressing this is particularly true of Egypt.
As this relationship evolves, the prime minister said his country is committed to protecting U.S. diplomats and their missions.
Until late Saturday, demonstrations near the U.S. Embassy in Cairo have been persistent and, at times, violent with scores injured and scores more arrested.
Still, the thousands of protesters represent a fraction of the Egyptian capital's total population of roughly 11 million people.
In Egypt's northern Sinai, a large number of security forces backed by tanks regained control of a base housing an international peacekeeping force that was breached Friday by Islamist militants.
Carrying automatic weapons, the militants burned trucks and a watch tower on the base, Egyptian media said.
The 1,500-troop Multinational Force & Observers mission has supervised the security of the Egyptian-Israeli peace treaty since 1979.
The force said in a statement that the demonstration outside its North Camp in el Gorah "turned violent."
"Individuals throwing Molotov cocktails and explosive devices breached the camp's perimeter. The breach was quickly contained by the professional actions of MFO personnel," the force said in a statement.
It reported eight minor injuries to force members and damage to vehicles and property. There had been a news report of an injury to an Islamist Bedouin, but the MFO said intruders left "with no known injury." The situation stabilized after Egyptian authorities "helped secure the camp's perimeter."
Militants have threatened the observers before, saying they would attack if they didn't leave.
"The MFO views these events with the gravest concern and is coordinating with Egyptian authorities regarding strengthened measures to secure MFO premises and personnel, and to ensure that the MFO mission may continue securely and effectively," it said.
Egyptian security has been fighting militants in Sinai since August. That's when 16 border guards were killed in an attack by Islamist militants.