Authorities have identified the armed assailant who killed six during a Monday rampage through a Nashville Christian school as 28-year-old Audrey Hale, a female identifying as male who authorities say once attended the school.

Nashville Metropolitan Police Chief John DrakeĀ addressedĀ reporters Monday evening, saying “we’ve identified the shooter as Audrey Hale, a 28-year-old female that lived in the Nashville area.”

Drake referred to Hale as “female,” butĀ toldĀ reporters that “she does identify as transgender.”

“We have investigations ongoing now … we have made contact with the father,” he said. “We have also determined there were maps drawn of the school in detail, surveillance, entry points, etc.”

He further confirmed the existence of a manifesto and other documentation such as maps that authorities are reviewing.

Hale inflicted six fatalities, three of whom were children and three of whom were faculty members. Drake confirmed that Hale attended the Covenant School “at one point,” but was unaware of the exact dates of her attendance.

Covenant School, which teaches students from preschool through sixth grade, has an enrollment of about 200 students, according to the school’sĀ website. The school was founded as a ministry of Covenant Presbyterian Church.

TheĀ Metropolitan Nashville Police Department saidĀ that one of its officers “engaged” the shooter, whom officers fatally shot. Officials initially said at aĀ press conferenceĀ Monday that the shooter “appears to be in her teens,” but theĀ police departmentĀ later clarified that Hale was the assailant.

She was armed with two AR-style rifles and one pistol, Drake said. Authorities believe she obtained them legally.

All three children were pronounced dead after arriving at Vanderbilt Medical Center, the spokesperson toldĀ ABC News.