note left in his hotel suite that was reportedly a series of numbers. so far no major clues about motivation. we have learned that the killer may have been casing other locations before sunday s massacre. we have also learned that the killer tried but failed to buy tracer ammunition at a gun show in the last few weeks. that would have allowed him to see what he was shooting more accurately. meantime, thousands of people turned out for a candlelight vigil honoring the fallen las vegas off-duty police officer. we know the identities of all 58 killed in the sense attack. let s begin with jean casarez. reporter: you re so right. law enforcement continues to not say anything about motive. a law enforcement source said it is is not believed his gambling hab habits had anything to do with the shooting.