After a 20-year-old mentally ill man who was armed with a knife was shot and killed by Detroit Police Officers Sunday morning, his family has demanded answers from the city's chief of police.

On Tuesday Detroit PD released video of the incident and Chief James White said Porter Burks refused to comply with the officer's orders to put the knife down. When he ran towards Detroit Police Officers, White said they had no choice but to shoot.

Around 5 a.m. on Sunday, police responded to the family's 911 calls about Burks. They said he was armed and they were concerned for other people's safety. He was also carrying a folding knife, which White said had an 8-inch blade on it, Fox 2 reports.

A crisis intervention trained officer asked him to drop the knife multiple times and asked Burks what he wanted.

After officers tried to convince him to drop the knife for four minutes, Burks ran toward the officers, who then shot him when he was about six feet away, investigators say. 

Police said Burks had schizophrenia and stabbed three family members - including a 7-year-old - the past three years. At one point, he was committed to a mental health institution, which he later escaped from. It took four officers to take him into custody and multiple Taser deployments during that escape.