jake ward, nbc news, san francisco. keeping a watch on unfolding disaster in brazil, heavy rain triggering mud slides leaving at least 78 people dead. families are joining search crews digging through debris. hundreds left homeless by this. a new warning about unruly passengers on planes. the faa says dozens of additional cases will be considered for prosecution. with that, here is tom costello. reporter: tonight, after a record number of disruptive and dangerous incidents on board commercial airliners, the faa sending 43 more cases to the fbi for criminal review, bringing that total to 80 since the start of 2021, including all out fist fights, flight attendants assaulted, restraining violent travelers. all strong males to the front