St. Louis school shooter had AR-15-style weapon, 600 rounds of ammo

• The police commissioner read an excerpt of the note: "I don't have any friends. I don't have any family. I've never had a girlfriend, I've never had a social life. I've been an isolated loner my entire life. This was the perfect storm for a mass shooting."
• The suspect also brought in "a large quantity" of ammunition strapped to his chest, some in a field bag that he carried, and other magazines that were found dumped in the stairwells, according to authorities.

Catch up quick: A teacher and a 16-year-old girl were fatally shot and seven students were wounded in the attack at Central Visual and Performing Arts High School, from which Harris graduated last year.

• The victims were identified as 10th-grader Alexzandria Bell and 61-year-old physical education teacher Jean Kuczka, per AP.
• Police said they killed the suspect in an exchange of gunfire.

The big picture: The tragedy was one of 581 mass shootings this year where at least four people were shot, not including the shooter, as of Monday, according to the Gun Violence Archive.