The 15-year-old who sowed death on Tuesday at his high school in the northern United States was "
", showing a "
, the sheriff in charge of investigate this umpteenth gun-related tragedy in the United States.
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He would shoot people at point blank range, often aiming at the head or the chest,
" said Michael Bouchard.
The death toll, which worsened on Wednesday, stands at four dead and seven gunshot wounds, almost all between the ages of 14 and 17.
The young murderer, arrested on the spot and identified as Ethan Crumbley, could spend the rest of his days in prison as he will be prosecuted as if he were of legal age, local prosecutor Karen McDonald has announced.
The police are convinced that his attack was "
", added this official, who detailed the charges against which Ethan Crumbley will respond, including "
" and "
act of terrorism
The shooting, perpetrated in a school in Oxford, deeply shocked this small town in the state of Michigan, north of the metropolis of Detroit.
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The shooter, carrying a Sig Sauer caliber 9 mm semi-automatic pistol, bought four days earlier by his father, opened fire shortly before 1 p.m. local time, methodically progressing through the school and shooting in particular on the doors of the classes where the students had barricaded themselves. He fired at least 30 bullets. "
He clearly came to kill people,
" Sheriff Bouchard summed up on CNN, adding that he had refused to explain the reasons for his murderous outfit.
The identities of the deceased adolescents have been made public: they are two girls aged 14 and 17 and two boys aged 16 and 17.
Other young victims remained hospitalized Wednesday, a 47-year-old teacher slightly injured in the shoulder having been able to return home.
Authorities are considering prosecution of the shooter's parents, prosecutor Karen McDonald said.
In addition to the gun used in the attack, bought on Friday during the big Black Friday promotions, guns were seized from the family home.
High school students at a wake.
JEFF KOWALSKY / AFP
Ethan Crumbley previously trained with the gun, posting photos of the gun and the targets he aimed on social media.
Tuesday, he would have brought the weapon in his backpack, without being worried.
Oxford High School does not have a metal detector gantry, as is often seen in the United States.
He opened fire on his way out of the toilet before pacing the halls, as the terrified students hid in the classrooms.
We know that he tried to enter the rooms, that he fired on the doors of several of them
", explained Sheriff Bouchard.
Right to silence
Seven bullets were still in the magazine when he went to the police inside the school, just minutes after the first call to the emergency number 911. Detained in a center for juvenile delinquents, the shooter "
invoked his right to silence
"after receiving a visit from his parents who asked him not to speak to investigators and hired a lawyer, police said.
Ethan Crumbley is under particularly strict surveillance, with authorities fearing he is waiting on his life.
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The six injured students were to varying degrees to the head, neck, leg, hip or torso. One of the victims, a 14-year-old girl, is in critical condition. She was placed on a life support after being operated on for chest and neck injuries, the sheriff said on Tuesday evening.
The massacre caused a shock among the population and all schools in the district will remain closed for the week.
Many high school students took part in a vigil of meditation on Tuesday evening.
Sheriff Bouchard denied Tuesday evening that his services were aware of threats targeting the school.
He also brushed aside rumors that the shooter had been harassed or had discipline issues.
Investigators were interested Wednesday in "
" found at his home, in which he expressed "