six people killed and dozens injured in string of weekend violence and mass shootings in US

In United States, at least six people including a Pennsylvania state trooper were killed and dozens injured in a string of weekend violence and mass shootings.

According to a Professor of Public Policy and statistics at Carnegie Mellon University Daniel Nagin, there’s no question there’s been a spike in violence, theories include the possibility that violence is driven by the prevalence of guns in America, or by less aggressive police tactics or a decline in prosecutions for misdemeanor weapon offenses.