It was not yet dawn when the armored vehicles, black and hulking like Batmobiles, rumbled into the residential neighborhood in Compton, Calif. A carjacker had stolen a vehicle in Los Angeles, exchanged gunfire with sheriff’s deputies and then ditched his prize, disappearing on foot into a dense patchwork quilt of pink houses.

The armored vehicles — and the heavily armed deputies inside them — were there to find and capture the armed carjacker.

Instead, they found a different black man, Donnell Thompson.

As the carjacker hid in a house several blocks away, Thompson slept in a stranger’s yard. He was 27 years old but possessed the mental faculties of a much younger man. He loved Uno, Michael Jackson and the Lakers. He was so gentle and shy he went by the nickname Little Bo Peep, his family told the Los Angeles Times. He had a clean record and was unarmed.

From inside one of the armored vehicles, however, Los Angeles County Sheriff’s deputies knew none of this. When Thompson didn’t respond to commands, the deputies detonated flash-bangs. When he still didn’t move, they hit him with foam bullets.

And when he allegedly ran toward them, a deputy atop the armored vehicle opened fire with an assault rifle, striking Thompson twice in the torso.

Thompson died. At almost the same instant, the real carjacker was arrested.

That was July 28. For almost two weeks, the Sheriff’s Department insisted that Thompson was a second suspect in the carjacking.

On Tuesday, the department admitted it had killed an innocent man.

“No question this is a terribly devastating event,” Capt. Steve Katz said during a news conference. He said there was “no physical evidence” connecting Thompson to the carjacking or shootout and promised a “thorough” and “complete” investigation into the shooting, according to the Associated Press.

Thompson’s relatives said they wanted more than an investigation, however. They wanted charges for the deputy who killed Thompson.

“I wouldn’t treat an animal this bad,” his sister Matrice Stanley told the Los Angeles County Board of Supervisors, according to the AP. “How is this justifiable?”

The incident is the latest in a string of fatal officer-involved shootings of black men across America. As in the recent police killings of Alton Sterling in Baton Rouge and Philando Castile in Falcon Heights, Minn., the shooting in Compton has prompted accusations of racial profiling and excessive force.

Stanley said she thought her brother’s race played a role in the shooting.

The incident also raises questions about the militarization of law enforcement, as departments across the country increasingly use armored vehicles and assault rifles to fight crime.

“In a civilian neighborhood, they bring an urban assault vehicle,” Brian Dunn, an attorney representing the Thompson family, told the Huffington Post. “The BearCat, it’s like a tank. Their response to this situation was so aggressive. Their tactics were so aggressive.”

The tragedy began in the early hours of July 28 when Robert Alexander, 24, allegedly stole a Honda Civic in Los Angeles, taking the car at gunpoint from its owner.

Fifteen miles to the south, in Compton, a sheriff’s deputy later spotted the Civic traveling erratically and decided to pull it over, according to the Los Angeles Times. The license plate showed the car was stolen. As a second patrol car arrived, the Civic drove off, punching through an elementary school’s fence.

As the car sped through Compton, Alexander allegedly shot at deputies, causing them to return fire. After the Civic crashed into a parked car, Alexander escaped on foot.

As he ran along Slater Street, the carjacker threatened two people on a front porch, according to the Times. He then entered the house, threw his gun under a couch, took his clothes off and climbed into a bed where an elderly woman — a complete stranger — was sleeping.

Despite the ruse, deputies found him and arrested him at 4:59 a.m.

Seconds later, a man living a few blocks away called 911. He told dispatchers he was taking out his trash when he spotted a figure lying in his front yard, the Times reported.

Although authorities already had Alexander in custody, there was confusion over whether he was the carjacker. A deputy who responded to the 911 call, meanwhile, saw that the figure in the man’s front yard resembled the carjacking suspect: a black man between the ages of 20 and 30 wearing dark pants or shorts and a basketball jersey.

The deputy radioed that he had found the carjacker who had fired at police, and the armored vehicles quickly arrived.

Thompson didn’t respond to commands, instead remaining motionless with one hand under his head and another concealed near his waist. An object that looked like a gun lay nearby, Katz said. When flash-bang explosives failed to wake Thompson, SWAT deputies shot him with foam bullets.

At that point, Thompson suddenly pushed himself to his feet and ran toward an armored vehicle, Katz said. An officer in the vehicle’s turret shot Thompson twice in the upper torso with an M4 assault rifle, the Times reported.

Stanley, Thompson’s sister, said she thought her brother didn’t respond to commands because he was afraid and confused, the AP reported. She called for the deputy to be fired, questioning why he opened fire when he was protected by the armored car.

Dunn, the family attorney, accused the Sheriff’s Department of “tactical blunders” and called the shooting a “mistake.”

“We’ve done our own investigation and have not heard anything to suggest that Donnell Thompson was in any way acting in an aggressive manner or in any way demonstrating that he posed a threat to anyone,” Dunn told the Huffington Post. Dunn also claimed: “He hadn’t committed a crime, he was not wanted, he had not done anything wrong, he was legally authorized to be where he was, he was legally authorized to be doing what he was doing, he wasn’t breaking the law and he wasn’t armed ― when you take that backdrop of facts it’s just not only a tragedy, but it’s a homicide, in every sense of the word.”

The attorney said he had filed a federal civil rights claim against Los Angeles County and was preparing to file a lawsuit as well.

Experts cautioned, however, that just because the Sheriff’s Department had admitted Thompson was innocent doesn’t mean the shooting will be declared unjustified.

“The commands being ignored, they used less-lethal force that was ineffective, the guy was running away. … Those factors are very relevant in leading them to believe, ‘This guy has done something wrong. This is our guy,’” Ed Obayashi, a Plumas County sheriff’s deputy and attorney who advises several law enforcement agencies in the state, told the Times.

Adding to concerns over the incident, however, are two other shootings of unarmed men by the same department in the past two weeks. A homeless man was shot on Aug. 2 while running from deputies. And a man caught tagging a house with graffiti was shot while hiding in a shower. Those shootings are also under investigation, the Times reported.

But it is the death of Thompson that has stirred anger and spurred protests.

“His age was 27, but mentally … he was probably 16,” Stanley told the Times.

“He was soft-spoken. He was gentle. What was the threat?” said cousin Larmar Avila, according to the AP. “I’m upset, I’m angry, I’m passionate, I’m emotional. It’s so much. All in one. And how do you expect us to act, when we’re patient, and we’re waiting and we’re waiting. We’re not going crazy. We’re waiting. Patiently. Twiddling thumbs. I’m shaking. I’m scared. I’m scared for my brothers. Scared for my family members. And it shouldn’t be like that.”

“Black lives matter,” said another sister, Antoinette Brown. “I just want justice for my baby brother.”

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