The Popular Front for the Liberation of Palestine is a "secular, Marxist-Leninist, nationalist Palestinian organization", which was founded and headed (until the year 2000) by Dr. George Habash, a Palestinian, Greek Orthodox Christian.

The PFLP has claimed responsibility for numerous "terrorist attacks", including suicide bombings.

http://www.reference.com/browse/wiki/Popular_Front_for_the_Liberation_of_Palestine

http://www.state.gov/r/pa/ho/pubs/fs/5902.htm