Saudi police arrested a Syrian resident in Riyadh after he posted a photo of himself on Facebook praising the recapture of his home city of Aleppo by government forces, according to a report in al-Riyadh newspaper.
A photo published with the report showed a man with his hand raised and his fingers pointed in a victory sign. His facial features were blurred to conceal his identity.
The newspaper said the resident, indentified as being in his 40s, was accused of publishing statements related to the war in Syria.
Saudi Arabia is a major regional backer of the rebel brigades fighting to oust Syrian President Bashar al-Assad. The rebels were dealt a crippling blow this week when Syrian government forces recaptured Aleppo.
Public expressions of dissent are considered criminal offences in the conservative Islamic kingdom, which has jailed people both for physical protests and for online statements.