update and back at 11:00 a.m. this morning and keeping tabs of everything that is going on out there. >>> good morning. bareknuckle brawl. >> i've been called a lot of things in my life. that was a first. >> hillary clinton and bernie sanders clash repeatedly during their most heated debate yet. >> wait a minute. wait a minute. i have stood on the debate stage with senator sanders eight prior times. >> excuse me. secretary, senator, please. >>> dr. jill biden speaking out in an exclusive interview about her husband's decision not to run. >> i feel, you know, maybe america missed an opportunity. >> and the republican party's fight with the memo over donald trump. the rnc chairman joins us live. >>> breaking overnight. aftershocks rattle japan following an earthquake that