The European Union says supporters of the Syrian government are flooding the European Parliament's Facebook page with hostile posts.
A Parliament spokesman says that since Tuesday night the page has been "flooded by posts which are coming from Syria and are probably well organized." Jaume Duch says many posts, which support Syrian President Bashar Assad, were probably generated automatically.
Assad is trying to repress an uprising, and human rights advocates say hundreds of people have been killed and thousands arrested.
On Monday, the EU imposed an arms embargo on Syria and visa bans and assets freezes on 13 regime members or supporters.
Duch said the Facebook page still functions but some posts now have more than 1,000 comments.