Uvalde, Texas – Before 18-year-old Salvador Ramos walked into Robb Elementary School on May 24 and massacred 19 innocent students and two teachers, there were warning signs that something was amiss.

Ramos was a loner with few friends. A teen who classmates describe as “aggressive,” and most concerning, a teen with a history of cruelty to animals. One of Ramos’ schoolmates said that “he would go to the park and try to pick on people and he loved hurting animals.”

Others claim that he used the French live streaming platform Yubo to upload videos of animal cruelty. One Yubo user told ABC News that Ramos would “put cats in plastic bags, suspend them inside, throw them at the ground and throw them at people’s houses.”

Jaime Arellano, a high school classmate, claims to have witnessed Ramos beating a dog. He recalled the disturbing incident, stating, “I remember there was one time we saw him beating a little dog senseless.”

Ramos sent messages via Facebook on the day of the mass shooting – messages indicating that he was going to shoot his grandmother, messages that he DID shoot his grandmother, and finally, a message that he was going to open fire at an elementary school. People who knew the teen admit that there were signs of mental instability that should have been reported; tragically, they weren’t.

The teen’s prior acts of animal cruelty, like those of Payton S. Gendron, the teen accused of killing 10 people in Buffalo, New York, perfectly highlight the documented link between animal abuse and human violence. It is one of the many reasons that Animal Victory pushes for substantial punishment for animal abusers. These early warning signs must be taken seriously to prevent even more death and destruction in the future.