About 100 protesters carried posters, including one calling for the immediate release of George Abdullah, who has been imprisoned for 28 years, and another bearing the likeness of U.S. President Barack Obama altered to look like the "Joker" character from Batman movies, The Daily Star newspaper in Lebanon reported.
"We aren't in the habit of apologizing to the Great Satan," another poster stated.
A French court granted Abdullah parole last month but the former Lebanese Armed Revolutionary Factions member, serving a life term, remains jailed pending an appeal by prosecutors.
Abdullah was arrested in 1984 and sentenced three years later for the killings of U.S. Lt. Col. Charles Ray and Israeli diplomat Yacov Barsimentov in Paris.
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