In an address at the African Methodist Episcopal Church in Philadelphia Friday, Clinton laid off the attacks on presumptive Republican nominee Donald TrumpDonald TrumpClinton fields email questions under shadow of Dallas attacks Clinton calls for unity after week of deadly shootings Poll: Trump's Hispanic support on par with Romney in 2012 MORE and focused on how she would address violence between police officers and their communities if elected president.
President Obama ordered flags flown at half-staff and denounced the attack as "vicious" and "despicable".
"There is no possible justification for these kinds of attacks or any violence against law enforcement", Obama said, just a day after he decried racial disparities in the criminal justice system after police shootings of African-American men in Louisiana and Minnesota.
Trump added that the violence of the past week proved it was "time, perhaps more than ever, for strong leadership, love and compassion. We must stand in solidarity with law enforcement, which we must remember is the force between civilization and total chaos", Trump said. "We must restore the confidence of our people to be safe and secure in their homes and on the street", Trump said in a statement.
Trump's carefully worded response was a striking contrast to his reaction to last month's Orlando gay nightclub massacre in which 49 people died.
In the aftermath of the police shootings of Alton Sterling in Louisiana and Philando Castile in Minnesota, a 25 year-old army veteran opened fire on a Black Lives Matter protest in Dallas.
Following the killing of Sterling in Baton Rouge, La., Clinton released a statement expressing her support for a federal civil rights investigation into the incident and said, "something is profoundly wrong when so many Americans have reason to believe that our country doesn't consider them as precious as others because of the color of their skin". We will pull through these tragedies."Clinton was scheduled to appear with Joe Biden on Friday at a rally and a fundraiser".
Clinton and Trump react to Dallas shooting Clinton posted this on Twitter, and did not tweet anything else for hours afterward.
She says more Americans need to walk in the shoes of black Americans and police officers alike. We have to do better than this. In the past, Trump has suggested that anti-police rhetoric could trigger attacks on officers. She said the same on Facebook.
Trump's statement on the Dallas attack appeared to have been crafted with the help of professional campaign staff, demonstrating Trump's willingness to rely on his still-small but growing communications team.
"It's a nightmare", Greenfield said.
The presumptive presidential nominees for both major political parties have postponed campaign events Friday, following the deadliest single day for US law enforcement since September 11, 2001.
"I'm going to be talking to white people - I think we're the ones who have to have to start listening to the legitimate cries that are coming from our African-American fellow citizens", she said. "May God protect them and bring peace upon Dallas", the former Republican presidential hopeful wrote. Some of them, you know, don't really have the resources that are necessary to keep training and retraining.
The chairman of Donald Trump's campaign in Virginia argued that Hillary Clinton is to blame for "essentially encouraging the murder" of five Dallas officers who were shot to death Thursday night.
Presumptive Democratic presidential nominee Hillary Clinton said on Friday that white people must do more to understand the experiences that African-Americans have had with police officers.