The Sandy Hook Elementary School shooting occurred on December 14, 2012, in Newtown, Connecticut, when 20-year-old Adam Lanza fatally shot 20 children and 6 adult staff members.[5][6] Prior to driving to the school, Lanza shot and killed his mother at their Newtown home.[8][11][12] As first responders arrived at the scene, Lanza committed suicide by shooting himself in the head.

The incident was the deadliest mass shooting at a high school or grade school in U.S. history and the second-deadliest mass shooting by a single person in U.S. history, after the 2007 Virginia Tech shootings.[13][14][15]

The shooting prompted renewed debate about gun control in the United States, including proposals for making thebackground-check system universal, and for new federal and state legislation banning the sale and manufacture of certain types of semi-automatic firearms and magazines with more than ten rounds of ammunition.[16][17]

A November 2013 report issued by the Connecticut State Attorney’s office concluded that Lanza acted alone and planned his actions, but no evidence collected provided any indication as to why he did so, or why he targeted the school.[18]

more: en.wikipedia.org/wiki/Sandy_Hook_Elementary_School_shooting

Sandy Hook Elementary School shooting
Police at Sandy Hook.PNG

Police arrive in front of the elementary school after the shooting.
Location Sandy Hook, Connecticut, U.S.
Coordinates 41°25′12″N 73°16′43″WCoordinates: 41°25′12″N 73°16′43″W[1]
Date December 14, 2012
c. 9:35 am – c. 9:40 am[2][3][4]EST (UTC−05:00)
Target Students and staff at Sandy Hook Elementary School
Attack type
School shooting, murder–suicide, matricide, spree shooting
Weapons Bushmaster XM15-E2S
Glock 20SF
Deaths 28 total; 27 at the school (including perpetrator) and perpetrator’s mother[5][6]
Non-fatal injuries
2[7]
Perpetrator Adam Peter Lanza[8][9]
Defender Victoria Leigh Soto, Dawn Hochsprung, Mary Sherlach, Lauren Rousseau, Rachel D’Avino, Anne Marie Murphy (all received Presidential Citizens Medal posthumously)[10]

Police response

First Response Timeline [41]
Time Event
9:35 am Shooter is believed to first enter SHES.
9:35:39 am First 911 call to Newtown Police is received.
9:36:06 am 911 dispatcher broadcasts shooting at SHES.
9:37:38 am Connecticut State Police dispatched to SHES.
9:39:00 am First Newtown police arrives behind SHES.
9:39:13 am Two more Newtown officers arrive at SHES.
9:40:03 am Last shot heard. Believed to be shooter’s suicide.
9:42:39 am Newtown police reports shooter’s car license plate.
9:44:47 am Newtown police officers enter SHES.
9:46:23 am Connecticut State Police arrive at SHES.
9:46:48 am Connecticut State Police enter SHES.

more: en.wikipedia.org/wiki/Sandy_Hook_Elementary_School_shooting

The first call to 911 was around 9:35 am. Newtown 911 police dispatch first broadcast that there was a shooting at Sandy Hook Elementary (SHES) at 9:36 am, about thirty seconds after they received the first call.[79] Connecticut State Police (CSP) were dispatched at 9:37 am.[63] Newtown police arrived at the school street at 9:39 am, approximately four and a half minutes after the 911 call and Connecticut State Police arrived at the school street at 9:46 am. Newtown police first entered the school at 9:45 am, approximately ten minutes after the first 911 call and approximately fourteen minutes after the shooting had started. This was approximately five minutes after the last shot was heard.[41] No shots were fired by the police.[3][80]

The Newtown police and Connecticut State Police mobilized local police dog and police tactical units, a bomb squad, and a state police helicopter.[81] Police locked down the school and began evacuating the survivors room by room, escorting groups of students and adults away from the school. They swept the school for other shooters at least four times.

At approximately 10:00 am, Danbury Hospital sent extra medical personnel in expectation of having to treat numerous victims. Three wounded patients were evacuated to the hospital, where two children were later declared dead.[82] The other was an unidentified adult.[7]

The New York City medical examiner dispatched a portable morgue to assist the authorities.[20] The victims’ bodies were removed from the school and formally identified during the night after the shooting.[83][84] A state trooper was assigned to each victim’s family to protect their privacy and provide them with information.

On December 4, 2013, seven 911 calls relating to the shooting were made public.[85]