(CNN) — New details are emerging about the US Army reservist who authorities say killed 18 people and wounded 13 others in Lewiston, Maine, last week<a class="excerpt-read-more" href="https://whdh.com/regional/maine/sheriffs-department-reports-show-law-enforcement-was-alerted-to-danger-posed-by-maine-gunman-months-before-shootings/">Read More</a>