Killed by Police so far (as of 9/23) in 2016*
So, right off the bat, it is not true to say that police have killed more blacks than any other group. That is not to say that it is proportional. Using 2016's data, blacks account for ~25% of persons killed by police, and account for ~13% of the population. In 2015 blacks killed accounts for ~27%. It's debatable if that is statistically significant, as a sample size of 844/1207 (depending on year) is not reliable for a population of about 324 million.
Besides mathematics, any amount of people killed by police is too many. Even one is too many. How do you fix this? What measures do you take? The Black Lives Matter site is dedicated to a strangely political platform rather than how to deal the issue of police brutality. It seems it has moved to Campaign Zero. These values and ideas are fair and agreeable. This only affects the deaths by police.
There is a greater problem with crime and crime involvement in the black community. They are only ~13% of the population; then they should commit roughly 13% of crimes. However, they commit 27% of all crimes, and the numbers are higher depending on the crime. They commit more than half of all murders and robberies. There's no way that this is the result of profiling. FBI Crime Statistics by Race
How do you solve this issue? There's no system that forces anyone to commit crime. This has to be solved of the community level. I don't think any political movement can change this.