Juan Ramon Ortiz

Juan Ramon Ortiz, 26, of Bayamon, Puerto Rico, was teaching a class as part of his graduate program in civil engineering at Virginia Tech.

The family's neighbors in the San Juan suburb remembered Ortiz as a quiet, dedicated son who decorated his parents' one-story concrete house each Christmas and played in a salsa band with his father on weekends.

"He was an extraordinary son, what any father would have wanted," said Ortiz's father, also named Juan Ramon Ortiz.

Marilys Alvarez, 22, heard Ortiz's mother scream from the house next door when she learned of her son's death. Alvarez said she had wanted to study in the United States, but was now reconsidering.

"Here the violence is bad, but you don't see that," she said. "It's really sad. You can't go anywhere now."