Police showed this picture Hill took on his cell phone holding the gun he allegedly used in the shooting
Michael Brandon Hill (Courtesy of Henry Co. Sheriff's Office)
DECATUR, Ga. -- Police said the "potential was there to have another Sandy Hook" at McNair Learning Academy.
The public defender for Michael Brandon Hill, the man accused of firing shots at McNair Discovery Learning Academy in DeKalb County on Tuesday, waived his first appearance in DeKalb Magistrate Court.
LISTEN | 911 calls from McNair learning center during shooting
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During a police press conference Wednesday, investigators said Hill got the gun from an acquaintance's home, and had nearly 500 rounds of ammo.
Tyrone Mitchell Sr. lives up the street from the school. He caught the scene on his phone and posted a video to his FB page.
VIDEO | Cell phone video of shooting at McNair Academy
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Officers from the Bureau of Alcohol, Tobacco and Firearms have the weapon and are trying to learn more about how Hill got it.
Police say Hill fired shots in the school before stepping outside and firing at police. Police did return fire.
Police are talking to Hill's friends and family to learn more about the suspect. They are also still trying to determine a motive.
Police did show a picture that Hill took on his cell phone holding the gun he used.
Twenty-year-old Hill, was arrested earlier this year for threatening to kill his brother.
A police report from Henry County Police shows that Hill was taken into custody on March 13 and charged with terroristic threats.
Hill's brother, Timothy Hill, who lives in McDonough, told police in late December 2012 that the suspect sent him a Facebook message saying "that he would shoot him in the head and not think twice about it," according to the police report.
Michael Hill was tracked down and then arrested by Henry County Police more than two months after making the Facebook threat.
READ | March Henry Co. police report on Hill
READ | December Henry Co. family violence incident report
Timothy Hill told police that Michael Hill suffers from mental issues. Timothy Hill also said he was in fear for his life, and that he did not know his brother's address.
11Alive's Center for Investigative Action talked to a Michael Brandon Hill's sister-in-law who told us that he had lived with her family a few years ago.
"I made sure he took his meds," Julie King said, adding, "he got angry every now and again but mostly kept to himself and liked to play board games."
A long time family friend Ben Haworth of McDonough wasn't surprised about Hill's arrest.
"It doesn't surprise me much. I knew he was going to snap. He set his family's house on few a few years back while they were all asleep in their house. They tried to get help. He was just always slapped on the wrist when he went to court because of his mental problems. He was never really punished by the judicial system for what he did," Haworth said.
We have not confirmed that Michael Brandon Hill was ever formally accused of setting fire to the family home but Haworth said his older brothers, Timothy and Dean, put it out.
Natasha Knotts, who helped lead the church Hill attended, Prophetical Word Church, says he was like a son to her. She says he called her "Mom". Knotts says her sister received a call from Michael Brandon Hill before the shooting and described what he said.
"I love you, tell ma that I love her. I appreciate everything you've done for me, and I don't make it out of this, I'll always love you,"Knotts told 11Alive.
There was a history of mental illness in the family. Hill's mother, 44 year old Rita Hill, died two years ago. The autopsy report said she had a history of depression and schizophrenia and suicidal thoughts.
She had Thanksgiving dinner with one of her son's in 2010 and on December 4th she was reported missing. 21 days later on Christmas day she was found in one of her son's backyards the same place where she was last seen.
Hill now faces charges of terroristic threats, firearm possession and aggravated assault on a police officer in Tuesday's shooting.
Hill's public defender waived his first appearance at DeKalb County Magistrate Court Wednesday afternoon. In a statement, Claudia Saari with the Office of the Public Defender said Hill is being represented by members of the office's Mental Health Division.