Two fatal police shootings of African-American men this week have sparked widespread outrage online, including from a range of famous figures from the worlds of music, film, television and professional sports, with Beyoncé, Drake, Lena Dunham, George Takei, Olivia Wilde, and Reggie Bush.

A Minnesota officer fatally shot a male driver during a traffic stop in Falcon Heights, a suburb of St. Paul, on Wednesday evening. A female passenger, who was accompanied by a young child, livestreamed what appears to be the immediate aftermath of the incident via Facebook.

On Thursday, family members identified the man as Philando Castile and the woman as his girlfriend, Diamond Reynolds. The child is described in the widely shared video as her daughter.

A day earlier in Louisiana, Alton Sterling was shot and killed by police outside a convenience store in Baton Rouge, where he regularly sold homemade CDs from a folding table.

The U.S. Justice Department has launched a civil rights investigation into the Sterling incident, which was also captured on video by at least two individuals on the scene.

The two shootings come as police use of force against minorities is under close scrutiny. Voices are calling out for nation-wide reform and training for law enforcement.

Others challenged the National Rifle Association and gun rights advocates on their lack of comment regarding given that Sterling, who police said was armed, lived in an open-carry state and Castile was a licensed gun owner who – according to his girlfriend's taped account – had alerted the officer who stopped him that he was carrying a firearm under permit as he complied with an order to produce identification.

Some reiterated that the problem of law enforcement's excessive use of force based on racial profiling is one for all citizens — regardless of racial background — to tackle together.