An Army veteran fatally shot five police officers and wounded seven other officers during Thursday night's downtown protest over the deaths of Sterling and Castile.
"Because you know killing back and forth at the end of the day is not going to solve the issue", Gilbert Rosa, a protester, told CNN affiliate WABC. I have cops in my family.
Their deaths - along with those of several African-Americans before them - spurred anger and debate over the use of force by police and questions over racial profiling.
In Texas, several state officials, including Lieutenant Governor Dan Patrick, lashed out at the group, directly linking its tone and tactics to the killings.
Ali, with the Black Lives Matter group in London, said it's more than a moment - it's a worldwide movement.
"I want to be a part of the movement, I'm here to stand with the people in America". The Dallas shooter, 25 year-old Micah Johnson, a veteran of the Afghan war, had experience both of USA violence against innocent populations in other parts of the world and white American violence against blacks in his own country.
According to Dallas Police Chief David O. Brown, Johnson "was upset about Black Lives Matter".
As many as 100 demonstrators were arrested in rallies held in Rochester and also in Louisiana - the scene of one of the recent police-involved shootings that claimed the life of 37-year-old Alton Sterling on July 5 that helped spark protests.
Simmering racial tensions seemingly boiled over after the deaths of first Alton Sterling, who was shot at close range by police in Baton Rouge, Louisiana, and then Philando Castile, who was killed by police during a routine traffic stop with his girlfriend and her daughter in the auto. After the massacre in Dallas, she said, "it turned on a dime".
As four black community organizers were surveying the piles of homemade sympathy cards, flowers and other tributes, a white man confronted them, shouting and cursing. "Does this get ignored?" she asked.
How will Dallas change Black Lives Matter? "We should reject all of this".
They say that no protesters were injured outside of some minor scratches sustained by two individuals who had resisted arrest. They were released and the police department will look into what happened.
Giuliani later added that Black Lives Matter is "instigators of violence".
On Thursday, before the protest in Dallas, Politico reported, Obama sought to strike a balance between law enforcement and the black community in the wake of the two shootings.
"Outrageous for RPD to handcuff two African American @13wham reporters for doing their jobs covering protests", he tweeted.
Black Lives Matter activist DeRay Mckesson, a public school administrator who is considered among the movement's loudest voices, was among 125 people arrested Saturday night in Baton Rouge. And we shouldn't dismiss the legitimate concerns of either by blithely asserting that all lives matter.