and in remembrance. a country now coming together, mourning loved ones lost. nightline will be right back. good evening and thanks so much for joining us. the mass shootings rocking the country to its core. 31 people dead and dozens more injured in two separate attacks over the weekend. now the hunt for answers as a nation once again tries to make sense of the senseless. run. reporter: scenes of chaos. eerily similar. go, go! come on! reporter: but more than 1500 miles apart. i miss her. i d give my life in trade for hers. reporter: stories of loss and heartbreak now spanning the nation. i just wish she would just wake up in a hospital and be like i m okay, it s just a little graze. but she s really gone. reporter: two deadly mass shootings leaving 31 dead and 53 injured. once again americans are coming to grips with this tragic reality. everyday people going about their lives, killed in cold blood. this time in el paso at a shopping center. and in dayton in