"Today, our Commonwealth and country stand in solidarity with the Jewish community of Pittsburgh. We mourn the loss of 11 lives at Tree of Life Synagogue in Squirrel Hill and pray for their families. We are also thankful for the work being done by federal, state, and local law enforcement who also responded and are assisting in the investigation. People across our nation are praying for the officers who were injured today. We stand with the victims and their families in this time of tragedy. Those of us in public office have an obligation to take actions that can reduce the likelihood of mass shootings. We must come together as a nation and meet this challenge." — U.S. Sen. Bob Casey, (D., Pa.), on Twitter