Exclusive - Scribbled note shows Nemtsov on trail of Russian deaths in Ukraine

People lay down flowers at the site, where Kremlin critic Boris Nemtsov was murdered on Friday night, during a march to commemorate him in central Moscow March 1, 2015. REUTERS/Tatyana Makeyeva

MOSCOW (Reuters) - It may have been the last note Boris Nemtsov ever wrote, a hurried scrawl in blue pen on a plain white sheet of A4 paper.

A day before he was shot dead near the Kremlin last week, the Russian opposition figure and his close aide Olga Shorina were discussing a sensitive investigation he was preparing into Moscow's backing for separatist fighters in eastern Ukraine.