UVALDE, Texas (CBSDFW.COM)- We are beginning to learn more about the mass shooting at a school in Uvalde, Texas that left 21 — children and adults — dead and many others critically injured.

The shooter who walked into Robb Elementary School and opened fire has been identified as 18-year-old Salvador Ramos, a resident of Uvalde. Law enforcement sources say he shot his grandmother, then drove to the school with a handgun and an AR-15. He continued his rampage until police arrived and was killed at the scene.

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According to Texas Department of Public Safety Lt. Christopher Olivarez, in addition to the weapons and ammunition, Ramos wore a “tactical vest” as body armor. He said all of the children and teachers who died were inside a single classroom where the shooter barricaded himself.

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We are also learning the names of some of the victims killed in the mass shooting.

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