A 30-year-old man died after police knelt on his neck for almost five minutes, his heartbroken family claim.
Angelo Quinto had been suffering from depression and paranoia when his sister, Isabella Collins called police to the family's California home fearing he would harm their mother.
Before police arrived to the scene, Isabella said their mother had been holding Mr Quinto to her chest for a number of minutes, claiming he "had already started to calm down".
However, the family claim when two officers from the Antioch Police Department arrived to the scene, they made no effort to understand the situation.
Instead, the family claim the officers immediately grabbed Navy veteran Mr Quinto from his mother's arms before he lost consciousness and was taken to a local hospital on December 23.
He was pronounced dead three days later, say lawyers representing the family who filed a wrongful death claim on February 18.
His mother Maria Quinto-Collins said her son was laying on the floor and not moving before officers rolled him over and carried his body out.
She claimed his face was bloody and says officers used a "George Floyd" technique of restraint as they placed their knee on his neck, reports CNN.
George Floyd, a black man, was killed during an arrest in Minneapolis in which white police officer Derek Chauvin pressed his knee against his neck while Mr Floyd lay handcuffed and face-down in the street.
Chauvin is charged with second-degree murder and second-degree manslaughter while former officers Tou Thao, J Alexander Kueng and Thomas Lane are each charged with aiding and abetting second-degree murder.
Lawyer for the Quinto-Collins family, John L. Burris, claimed a similar method of restraint led to the unlawful death of Mr Quinto.
Mr Burris said: "These Antioch police officers had already handcuffed Angelo but did not stop their assault on the young man and inexplicably began using the 'George Floyd' technique of placing a knee on the back and side of his neck, ignoring Mr. Quinto pleas of 'please don't kill me."
Isabella Collins she will 'never not feel bad' for calling police on her brother, but said she believed their arrival would help de-escalate the situation.
Mr Quinto's official cause of death is still unconfirmed and the incident is under investigation by the Contra Costa County District Attorney's office.
