A black motorist was shot at close range and seen bleeding to death in a distressingly graphic video viewed online by two million people Thursday, the second case of racism-tinged police violence to rock America in as many days.

A four-year-old girl witnessed the shooting of Philando Castile from the back seat of the car in a town near Minneapolis, Minnesota on Wednesday, as her mother -- the victim's girlfriend -- livestreamed the shocking scene.

"Oh my God, please don't tell me he's dead, please don't tell me my boyfriend just went like that...," the woman, identified on her Facebook page as Lavish Reynolds and also known as "Diamond," is heard telling a police officer pointing a gun through the car window.

"You shot four bullets into him, sir. He was just getting his license and registration, sir."

Pulled over apparently for a broken tail light, Castile had informed the officer that he was carrying a licensed gun, according to his girlfriend's filmed account.

In the background, an officer is heard shouting: "I told him not to reach for it. I told him to get his hands up."

Shocked family members immediately demanded justice for the 32-year-old Castile, a school cafeteria worker, whose mother described him as a law-abiding citizen who kept out of trouble.

"I think he was just black in the wrong place," Valerie Castile told CNN. "Every day you hear of another black person being shot down, gunned down by the people that are supposed to protect us."

A day earlier, a black father of five died in another police shooting captured on video, that time in Louisiana. Alton Sterling was pinned to the ground and shot several times at point blank range, prompting the launch of a federal civil rights investigation.

"We're being hunted every day. It's a silent war against African-American people as a whole," Castile said.

(AFP)