New court documents show the pupil confessed to the attack and outline how he took his mother's gun.
The six-year-old student who shot his teacher in the US earlier this year, boasted about the incident saying "I shot [her] dead", unsealed court documents show.
While being restrained after the shooting at a Virginia school, the boy is said to have admitted "I did it", adding "I got my mom's gun last night".
His teacher, Abigail "Abby" Zwerner - who survived - filed a $40m (£31.4m) lawsuit earlier this year.
The boy has not been charged.
The boy's mother, however, Deja Taylor, has been charged with felony child neglect and misdemeanour recklessly leaving a loaded firearm as to endanger a child.
In Ms Zwerner's lawsuit, filed in April, she accuses school officials of gross negligence for ignoring warning signs and argues the defendants knew the child "had a history of random violence
The documents also mention another incident with the same student while he was in kindergarten. A retired teacher told police he started "choking her to the point she could not breathe".
Idgaf. If a five year old is choking me till the point I can’t breath there will be (appropriate) consequences. He spends 8 hours a day at that school you bet your ass he will behave in my class.
We know ydgaf, that's why you keep leaving these braindead comments. The world in your head has little correlation with the one we find ourselves living in.