Many major cities around the United States implement curfews meant to prevent a second night of riots, including Atlanta, Chicago, Cleveland, Columbus, Denver, Los Angeles, Miami, Minneapolis, Milwaukee, Philadelphia, Pittsburgh, Portland, Rochester, Salt Lake City, and Seattle.
A gunman opens fire at the Tree of Life - Or L'Simcha Congregation synagogue in Pittsburgh, Pennsylvania, killing at least 11 people. The perpetrator 46-years old Robert Bowers was an active user of the social media service Gab where he had posted anti-Semitic and racist content as well as one before the shooting that said "HIAS likes to bring invaders in that kill our people. I can't sit by and watch my people get slaughtered. Screw your optics, I'm going in".
Researchers at Pittsburgh, Pennsylvania's Carnegie Mellon University (CMU) successfully use a 3-D printer (specifically, a fused deposition modeling (FDM) printer) to produce hair-like strands, inspired by the use of a hot glue gun to produce gossamer strands. Also, using certain materials (like collagens, alginates, and fibrins), with a 3-D printer and special bioprinting techniques, another team at CMU produced human coronary arteries and small, embryonic-like human hearts.
Pittsburgh police arrest Ryan Williams for the October 18, 2014 McKeesport, Pennsylvania arson attack and charge him with arson, burglary, and six counts of criminal homicide. The victims include four children ages 2 through 7.