Egyptian Antiquities Minister Zahi Hawaas says authorities have secured Egypt's museums and monuments following several cases of looting late last week.
Hawaas told CNN on Tuesday that Bedouins have returned almost all artifacts stolen by an armed gang from a warehouse in the Sinai peninsula.
He also told the Associated Press that two mummies initially thought to have been damaged by looters at Cairo's Egyptian Antiquities Museum were later found to be intact.
Authorities detained 10 people who raided the museum Friday, stealing valuables from its gift shop and damaging artifacts in a search for gold. The looters smashed 13 glass showcases and threw about 70 artifacts on the floor. Hawaas said the damaged items can be restored.
U.N. cultural agency UNESCO is appealing to Egypt to protect its heritage as political turmoil sweeps the country.
In a statement Tuesday, UNESCO director Irina Bokova issued a "solemn" request for "all necessary measures" to safeguard treasures in Cairo, Luxor and other cultural and historical sites in the country.
She said the value of the 120,000 pieces in the Egyptian Antiquities Museum is "inestimable" because it represents Egyptians' cultural identity.
Bokova also expressed concern about harassment of journalists by Egyptian authorities and government moves to restrict Internet access in the country. She says it is "crucial" for Egyptian and foreign journalists to be able to inform the public from an objective perspective.
Harvard University Egyptologist Peter Der Manuelian said he is disheartened to hear reports of looting at the pyramid fields of Saqqara and Abu Sir.
He said he and other U.S. experts are communicating with colleagues in Egypt via land lines and trying to raise awareness of the problem among Egyptian officials.
Der Manuelian said law enforcement agencies in Egypt and abroad should be vigilant about the possible trafficking of looted artifacts, particularly in light of the uncertain situation at Cairo's airport.