UPDATE: Md. school shooter died from self-inflicted gunshot

(PHOTO: CNN)

ST. MARY’S CO. – The St. Mary’s County Sheriff’s Office has released information detailing what happened the morning of the Great Mills High School shooting which cost 16-year-old Jaelynn Willey her life.

Evidence shows that Austin Rollins, 17, fired a single shot from a handgun at 7:57 p.m. down Hallway F of the school.

Deputies say that bullet struck Jaelynn Willey and Desmond Barnes.

Rollins continued to walk through the school, and was then confronted by a School Resource Officer, Deputy First Class Blaine Gaskill, in Hallway D.

Deputies say Rollins fired one fatal shot to his own head at the same time Officer Gaskill fired a non-fatal shot to Rollins’ weapon in his hand.

The Sheriff’s Office released a map outlining Rollins’ and Gaskill’s movement.

(PHOTO: St. Mary’s Co. Sheriff’s Office)