Yes statistics clearly show black on black killings are higher in number than police on black killings. This is in line with stats that show intraracial killings in general are more likely, regardless of the race in question (
https://ucr.fbi.gov/crime-in-the-u....f_vicitm_by_race_and_sex_of_offender_2013.xls). Here, there is an 83% chance of a white person being murdered by another white person, and a 90% chance of a black on black murder.
For black on black murder, there is a general trend that this is becoming less prevalent since 1990, and is lower vs the 1960s including the civil rights movement era (
http://www.cdc.gov/nchs/data/hus/2014/032.pdf). So although intraracial murder is a problem generally, it shouldn't have an impact on a movement aimed at equality for black people. And neither should the fact that males commit the vast majority of crimes. Should we ignore male violence? Of course not. But BLM doesn't need to be responsible for minimizing all black killings in the USA. Just as charities should exist for illnesses other than cancer or heart disease, despite being less likely to be a cause of death.
To the point of male murders and murderers or kills by police, yes all stats I have seen state a man is far more likely to be a killer or be killed than a woman. But this is off topic, despite being a very good candidate for a another thread on the matter. Again, BLM doesn't have to concentrate on all male killers or victims.
Police kill more white people than black - in sheer number terms yes, but proportionally that is not the case. Black males are more likely to be killed by police in the US (
https://www.theguardian.com/us-news/2017/jan/08/the-counted-police-killings-2016-young-black-men).
The case of witnesses Anthony O'Grady and Sunny Khalsa does seem to be a point where either memories are misrecalled or facts are falsified. Honestly I don't know which is applicable here, I guess you could argue either way depending on what point you want to make. Is this a one off incident or are there other examples to support a trend (genuinely curious)?
To the point of the higher proportion of black people killed by police is due to black people more likely to be involved in crime. Well, black people are more likely to have less wealth than white people in the US (
http://www.epi.org/publication/black-white-wage-gaps-expand-with-rising-wage-inequality/#epi-toc-4). As this study shows (
https://academic.oup.com/sf/article...tremely-Disadvantaged-Neighborhoods-and-Urban) there is a strong correlation between wealth and crime rates, but shows little race correlation when wealth is taken into account.