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Experts confront multiple explanations for surge of killings

FILE - In this Friday, July 14, 2016 file photo, police stand by as medical personnel attend a person on the ground, right, on the Promenade des Anglais in Nice, southern France, next to the lorry that had been driven into crowds of revelers late Thursday. The relentless series of mass killings across the globe poses a challenge for experts trying to analyze them without lapsing into faulty generalizations. Terms like contagion and copycat killing apply in some cases, not in others, they say, and in certain instances perpetrators' terrorist ideology intersects with psychological instability. (AP Photo, File)
FILE - In this Friday, July 14, 2016 file photo, police stand by as medical personnel attend a person on the ground, right, on the Promenade des Anglais in Nice, southern France, next to the lorry that had been driven into crowds of revelers late Thursday. The relentless series of mass killings across the globe poses a challenge for experts trying to analyze them without lapsing into faulty generalizations. Terms like contagion and copycat killing apply in some cases, not in others, they say, and in certain instances perpetrators' terrorist ideology intersects with psychological instability. (AP Photo, File) FILE - In this Friday, July 14, 2016 file photo, police stand by as medical personnel attend a person on the ground, right, on the Promenade des Anglais in Nice, southern France, next to the lorry that had been driven into crowds of revelers late Thursday. The relentless series of mass killings across the globe poses a challenge for experts trying to analyze them without lapsing into faulty generalizations. Terms like contagion and copycat killing apply in some cases, not in others, they say, and in certain instances perpetrators' terrorist ideology intersects with psychological instability. (AP Photo, File)

NEW YORK (AP) – The relentless series of mass killings across the globe poses a challenge for experts trying to analyze them without lapsing into faulty generalizations. Terms like contagion and copycat killing apply in some cases, not in others, they say, and in certain instances perpetrators’ terrorist ideology intersects with psychological instability.

Some of the attacks, such as the coordinated assault on multiple targets in Paris last November, were elaborately planned operations by Islamic State adherents. However, they may have contributed to some of the other attacks by troubled individuals with no established ties to the militant group.

J. Reid Meloy, a San Diego-based forensic psychologist who has served as a consultant to the FBI’s Behavioral Analysis Program, said some of the attackers appear to have identified with Islamic State as an outlet for their own seething emotions.

“In virtually every one of these cases, there was a deeply held personal grievance – loss, anger, humiliation,” Meloy said. “When they come across Islamic State material, they’re stimulated by that. They can take their personal grievance worldwide.”

Meloy said two different syndromes could be surfacing in the series of attacks – contagion, in which one attack rapidly inspires imitation attacks, and copycat incidents, in which an individual seeks to emulate a previous perpetrator.