Syria is blocking Facebook in an attempt to squelch dissent, Syrian activists and bloggers say. And Facebook is just the most visible part of a broad crackdown on the Internet.
"Facebook helped further civil society in Syria and form civic groups outside government control. This is why it has been banned," women's rights advocate Dania al-Sharif told Reuters.
"They cut off communications between us and the outside world. We are used to this behavior from our government," said Mais al-Sharbaji, who set up a Facebook group for amateur Syrian photographers.
Reuters says Syria has intensified a censorship drive in recent months.
"We have asked officials and they said Facebook could become a conduit for Israeli penetration of our youth, but the real reason for blocking the forum because it provides for criticism of the authorities," Ammar al-Qurabi, head of the National Association for Human Rights, said.
President Bashar al-Assad allowed the Internet into Syria when he became president in 2000. He was previously head of the Syrian Computer Society. Syria has been under "emergency rule" since 1963.