Just hours after being repeatedly tasered and held in the street by Los Angeles police, Patrisse Cullors' relative, who was one of the movement's co-founders, died.
31-year-old parent and teacher Keenan Anderson passed away in a Santa Monica hospital.
The incident that happened on January 3 has body camera footage made public by the LAPD.
The video shows Mr Anderson asking for help as police officers restrain him.
His cries of “They’re trying to George Floyd me!” may be heard at once. — Alluding to the killing of a black man by a police officer in Minneapolis, Minnesota, in May 2020.
It has not yet been revealed what killed Mr Anderson, a resident of the Washington, DC, area who was in Los Angeles on vacation.
Three black males and one brown man have been killed in LAPD encounters in the past week, and this footage adds to the mounting pressure on the department.
Beginning in January, police officers fatally shot Takar Smith, 45, and Oscar Sanchez, 35.
Karen Bass, mayor of Los Angeles, described the events as “very troubling.” The police department has said that it is looking into the deaths of the three guys.
The officers who tasered Mr Anderson responded to a report of a car crash at around 15:00 local time.
At a news conference on Wednesday, police chief Michel Moore said that Mr Anderson had hit and run after a car accident, which is a crime.
He added that Mr Anderson had tried to “get into another person’s car without their permission” to flee the scene.
Police arrive to find Mr Anderson in distress, and he tells the first officer that “somebody is trying to kill me,” even though there is no apparent danger.
Mr Anderson follows instructions to sit down, but as additional police officers arrive, he gets up and rushes into the street.
When the police arrive to apprehend Mr Anderson, he initially cooperates with them but then becomes belligerent and finally terrified, yelling, “please” and “help” and “they’re trying to George Floyd me!”
Officers had previously warned Mr Anderson to “stop [resisting arrest], or I’m going to tase you” before using the stun gun on him for around 30 seconds. Other officers were restraining him. About five seconds later, he’s tasered once more.
According to the police, Mr Anderson was taken to the hospital about five minutes after he was tasered. Police say that he went into cardiac arrest and died about four and a half hours later.
The LAPD’s toxicology results confirmed that Mr Anderson tested positive for cannabinoids and cocaine in his blood. The Los Angeles County coroner’s office will compile an independent report.
The death of Mr Anderson has reignited calls for police reform, with some demonstrators arguing that officers armed with firearms have no place in responding to vehicle crashes.
“My cousin was asking for help, and he didn’t receive it,” Patrisse Cullors, co-founder of Black Lives Matter and Mr Anderson’s cousin, told the Guardian.
“My cousin was scared for his life. He spent the last ten years witnessing a movement challenging the killing of black people.
“He knew what was at stake and he was trying to protect himself. Nobody was willing to protect him.”
Ms Cullors and others demand that the LAPD’s top cop step down.
Mr Moore claimed he had released the Mr Anderson video quickly owing to public demand. This process, he explained, often takes 45 days.