NASHVILLE -- The suspect who allegedly shot and killed six people at a private Christian school in Nashville, Tennessee, last week had been planning for "months to commit mass murder at The Covenant School," police said, citing the suspect's journals.
The suspect -- identified by police as 28-year-old Audrey Hale, a former Covenant School student -- fired 152 rounds during the March 27 mass shooting, Nashville police said in a statement Monday.
Hale was armed with two assault-style rifles, a handgun and "significant ammunition" at the time of the attack, according to police. Authorities said Hale owned seven legally purchased guns from five different local stores.
The seven guns that were confiscated by the authorities were purchased between Oct. 30, 2020 and June 6, 2022, a law enforcement official told ABC News. The last weapon purchased was an AR-15 style weapon, according to the official.
Hale was shot and killed by police inside the school. The two officers who shot at Hale discharged four rounds each, according to police.
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A motive remains unknown, but authorities determined that "Hale considered the actions of other mass murderers," police said.
Hale had a detailed map of the school as well as "writings and a book we consider to be like a manifesto," Metropolitan Nashville Police Chief John Drake told ABC News last week.
Hale's writings, left behind in a car at the scene and a bedroom, are under review by Nashville police and the FBI, authorities said Monday.
A police spokesperson said Hale was assigned female at birth but pointed to a social media account linked to Hale that included the use of the pronouns he/him.
Funerals are underway for the three children and three adults killed. The victims were identified as 9-year-old Evelyn Dieckhaus, 9-year-old Hallie Scruggs, 9-year-old Will Kinney, substitute teacher Cynthia Peak, school custodian Mike Hill, and the head of the school, Katherine Koonce.
ABC News' Stephanie Wash, Pierre Thomas and Luke Barr contributed to this report.