The city of St. is located in the northeastern part of the United States The FBI background check that stopped the 19-year-old from buying a gun from a licensed dealer stopped him from buying the rifle that he used to kill two people.

St. Louis police said that Harris tried to buy a gun from a licensed dealer. Police said the sale was blocked by an FBI background check. It wasn't immediately returned.

Police said that Harris bought the rifle used in the school shooting from a private seller who had purchased it legally in 2020.

Missouri does not have a red-flag law that would keep firearms out of the hands of people who are a danger to themselves or others. Police didn't have clear authority to temporarily seize the rifle when they responded to the suspect's home when his mother called.

Harris' mother called police after she found a gun and wanted it taken away. A person known to the family took possession of it.

Harris regained the gun. That is being investigated.

Within minutes, police responded to the call. The man who graduated from the school was shot and killed by officers. He had a lot of bullets with him.

Fourteen-year-old Alexzandria Bell and her teacher Jean Kuczka died in the attack. The injuries are not thought to be life threatening.

Harris was believed to have intended to target. They didn't say if any of the victims were included.

The police commissioner said that Harris' mother was devastated by the shooting. Sack said at a news conference that she and other relatives had dealt with Harris' mental health issues. They checked his room to make sure he didn't have a weapon, as well as monitoring his mail.

Harris lamented in a note that he had no friends, no family, no girlfriend and a life of isolation. It was the perfect storm for a mass shooting.

Sack said that mental health is a challenge. It's difficult to tell when someone is going to act out or be depressed.

One of the schools that was evacuated as the shooting unfolded was the Central Visual and Performing Arts. Central has more than 300 students.

A security guard saw Harris try to get in the locked building. Sack doesn't know how Harris got inside.

Four minutes after the call, some of the off-duty officers showed up. During the chaos of students, teachers and staff fleeing, some officers asked where the shooter was. Harris was found on the third floor barricaded in a classroom. The police said that when Harris shot at them, they shot back and broke through the door.

According to a list of shootings compiled by Education Week, the St. Louis shooting was the first school shooting to involve more than one death.