Police in St. Louis, Missouri say the teen gunman who killed a teacher and a student on Monday left a notebook in his car illustrating why his life was “a perfect storm for a mass shooting,” including a lack of friends, girlfriend and family.  

Orlando Deshawn Harris, 19 stormed the Central Visual and Performing Arts High School and fatally shot  Alexandria Bell, 15, and physical education teacher Jean Kuczka, 61, while seriously wounding six others. 

Police did not say how Harris entered the locked building armed with an AR-15 style weapon and 600 rounds of ammunition, enough to kill hundreds.  His gun jammed during the attack, and Harris was shot and killed by police after firing on them.   

Many of the students had barricaded themselves in classrooms and some jumped out windows, media reports said.

The shooting was one of dozens in U.S. schools that caused death or injuries this year alone. One of the deadliest took place in May when a gunman killed 19 children and two adults in Uvalde, Texas.

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