and that she is cooperating with authorities. police say they have every reason to keep her here and to continue questioning her pause she is such an important witness. russian media says there's a computer image of what the assailant might look like based on eyewitness testimony. they say that they believe that the assailant was a male who was between one meter 70 and one meter 75 tall. that's between about 5'6" or 5'7" that he was wearing dark blue jeans and had very short brown hair. police say they're looking for additional eyewitnesses. they put out a reward of throw million rubles about $50,000, for any clues that would lead to the avenue are of the assailant, cnn, moscow. nemtsov was outspoken against russian president putin. last year nemtsov talked with cnn's an anthony bourdain about russian corruption and what you says happens when you oppose president putin.