safety upgrades amid recent incidents. last month a woman was left bloodied by a foul ball in chicago. in may, a cubs player was visibly distraught after his foul ball struck a 2-year-old girl in the head fracturing her skull. and last season a 79-year-old woman died from head injuries after being hit in dodger stadium. >> you want to have a good interaction with the fans, getting autographs and stuff. but at the end of the day we want to make sure everybody comes out of the games healthy. >> reporter: to ensure that a day at the ball park doesn't end with a trip to the hospital. ron mott, nbc news, chicago. tonight an urgent man hunt is under way for a killer after an american woman and her boyfriend were found murdered. it happened while the two were traveling in one of the most remote parts of canada. late word now the new disappearance of two teens could be connected. morgan chesky with details. >> reporter: tonight investigators believe this canadian highway may hold answers in hay murder mystery. north carolina native china on a road trip with her boyfriend lucas fowler when their 1986 chevy van