Castile was pulled over Wednesday night in Falcon Heights, near St. Paul, for a broken tail light, Dayton said. A woman, later identified to be his girlfriend, caught the aftermath on cellphone video after Castile was shot multiple times.
Black residents of Minnesota have been reaching out to Dayton to share details of what they experience when they are pulled over by police, and the governor added he doesn't think Castile would have been killed if the driver and passengers in the car were white.
Dayton said no one should be shot for a broken taillight, calling the ordeal "unacceptable by all the standards and values that I hold dear."
"My sense of outrage was very real," he said.
After Castile was pulled over, he informed the police officer that he was carrying a gun, Reynolds said. After Reynolds informed the officer that he was licensed to carry, Castile was shot multiple times, she said.
Cellphone video taken by Reynolds shows Castile sitting in the car with a shirt that appears to be soaked in blood. The officer can be heard saying, "I told him not to reach for it. I told him not to get his hand out."
Dayton also expressed disgust that after the shooting, fellow officers tended to their officer who shot Castile, who sat bleeding in the car.
"No one tended to his condition," Dayton said. Castile's girlfriend, Diamond Reynolds, was handcuffed and taken to the police station with her 4-year-old daughter, he said.
Dayton called Diamond's presence throughout the ordeal "extraordinary" and poignant."
"Justice will be served, but it's going to take some time to do that" Dayton said. "We're not vigilantes. We can't deny due process."
This afternoon, several Minnesota state officials wrote a collective letter to U.S. Attorney General Loretta Lynch expressing their "sadness" over Castile's death and urging the Department of Justice to launch a full and thorough investigation into the circumstances surrounding his death.
"A full and thorough accounting of the facts is necessary in order to secure justice for Philando’s family and his loved ones," they wrote. "While we appreciate that the Department has offered to assist the BCA’s efforts as necessary, we believe it is important that the Department immediately initiate a federal investigation."
The letter was signed by Dayton, Minnesota Lt. Gov. Tina Smith, Sen. Amy Klobuchar, Sen. Al Franken, Congresswoman Betty McCollum and Congressman Keith Ellison.