A new study suggests that many of the deadly school shootings in the United States over the past 10 years could have been prevented.
Most students who carried out such an attack had shown threatening or suspicious behavior, but were not reported to law enforcement, the study found.
The U.S. Secret Service reported the findings last week.
The study was based on an in-depth examination of 41 incidents of "targeted school violence." All of the attacks happened over a 10-year period from 2008 to 2017.
The Secret Service's National Threat Assessment Center collected information from police reports, as well as public and non-public investigation records.
The findings will be used to train school officials and law enforcement to better identify students who may be plotting an attack.
Lina Alathari is head of the National Threat Assessment Center. She told The Associated Press that most school shootings "are not sudden, impulsive acts where a student suddenly gets disgruntled." She added that "the majority of these incidents are preventable."
In 80 percent of the shootings, the attacker's behavior was so worrisome to others that it made them express concern about "the safety of the attacker or those around them."
The study found that the shootings took place quickly and often ended within 60 seconds or less. Law enforcement rarely arrived while the attack was happening. Attacks generally started during school hours and happened in a single area, such as a dining hall, restroom or classroom.
Most of the attackers were male, but seven were female. Researchers reported that 63 percent of the attackers were white. Fifteen percent were black, 5 percent Hispanic and 2 percent American Indian or Alaska Native.
The attackers most often used guns, but knives were sometimes used. Investigators said most of the weapons came from the homes of the attacker.
The report identified warning signs that school officials, families and other students could use to help them recognize a possible attacker. These include signs of increased anger, a clear interest in weapons and violence, depression or isolation, self-harm or sudden behavioral changes.
The study found most U.S. schools have security cameras as well as planned lockdown measures for shooting situations. However, only 17 percent of the schools had a system in place where students or families can directly contact officials about a student in crisis.
The study was launched following the 2018 shootings at Marjory Stoneman Douglas High School in Parkland, Florida.
The fathers of three students killed in the attack attended a media event timed to the release of the study.
Tony Montalto, whose daughter Gina Rose died in the Florida shooting, said the research was invaluable and could have helped her school prevent the attack.
"My lovely daughter might still be here today," he said. "Our entire community would be whole instead of forever shaken."
Montalto urged other schools to pay close attention to the findings. "Please, learn from our experience. It happened to us, and it could happen to your community, too," he said.
Words in This Story：
impulsive – adj.doing things suddenly and without careful thought
disgruntled – adj.angry
isolation – n.the condition or state of being separate from other people, places or things
lockdown– n.a condition in which people are temporarily barred from entering or leaving a restricted area.
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