Complex sentence: When the riot police arrived, activity in Kenmore Square quickly calmed down, but elsewhere violence continued and tragedy struck with the death of Victoria Snelgrove, who was killed near Fenway Park by a less-lethal crowd control projectile fired by the Boston Police.
Split into simpler sentences: When the riot police arrived, activity in Kenmore Square quickly calmed down, but elsewhere violence continued. Tragedy struck with the death of Victoria Snelgrove, who was killed near Fenway Park by a crowd control projectile fired by the Boston Police.