BLOOMINGTON, Ind. -- Eleven people died Saturday when a gunman opened fire during a service at the Tree of Life Synagogue in Pittsburgh. The accused shooter had a history of posting vicious anti-Jewish comments on social media sites.

Günther Jikeli and Mark Roseman from the Borns Jewish Studies Program at Indiana University Bloomington are available to speak with news media about the history of antisemitism and its recent proliferation on social media.

Jikeli's areas of expertise include antisemitism, right-wing extremism in Germany and radicalization. A historian and sociologist of modern Europe, has been visiting associate professor at the Institute for the Study of Contemporary Antisemitism at Indiana University since August 2015. He is a research fellow at the Groupe Sociétés, Religions, Laïcités at the Centre National de la Recherche Scientifique, Paris.

In 2013, he was awarded the Raoul Wallenberg Prize in Human Rights and Holocaust Studies by the International Raoul Wallenberg Foundation and Tel Aviv University. His latest book is "European Muslim Antisemitism. Why Young Urban Males Say They Don't Like Jews."

Roseman's areas of expertise include the history of the Holocaust, antisemitism, 20th-century German history, European post-1945 reconstruction and comparative history, including German-Japanese comparisons. The director of the Borns Jewish Studies Program at IU Bloomington, he is a historian of modern Europe, with particular interests in the history of the Holocaust and in modern German history.

His publications have covered a wide range of topics in German, European and Jewish history, including Holocaust survival and memory; Nazi policy and perpetrators; the social impact of total war; post-1945 German and European reconstruction; and Jewish and other minorities in modern German history. He is the author of "The Wannsee Conference and the Final Solution: A Reconsideration," considered the definitive account in a pivotal Nazi discussion of the fate of Europe's Jews.