"He stood there and allowed the gun to be pointed right at him so there would be no more young kids hurt," Gov. Susana Martinez told 1,500 or so people at a prayer vigil late Tuesday.
Others teachers scurried to lock kids in classrooms while students in the gym where the shooting took place dove under bleachers and took cover, said Andrea Leon, a 13-year-old eighth grader at the school.
Leon says she was walking toward the gym, where students gather before class, when she heard the gun shots. She said she knew they were real, "but some people were laughing because they thought it was fake."
"I guess they had been through many drills," she said.
Roswell Superintendent Tom Burris said the staff and students had participated in active shooter training and responded appropriately.
Police and schools nationwide adopted "active shooter" policies after Columbine High School students Eric Harris and Dylan Klebold killed 12 classmates and a teacher, and wounded 26 others before killing themselves in the Littleton, Colo., school's library in 1999. Police waited 45 minutes for a SWAT team to arrive before entering the school. Officers now are trained to confront a shooter immediately.
Chaves County Sheriff Rob Coon says his department does training at every public and private school in the county. At the core, he says, the training focuses on getting children to a safe place.
Coon said teachers now know they likely are going to be the first line of defense, especially in rural areas where law enforcement can be miles away. And while having teachers confront armed students is not part of the training, Coon called Masterson's actions commendable.
"It's not a good thing to do that, but it was a very brave thing the teacher did yesterday," the sheriff said. "He talked that kid into putting the gun down where that kid could have very easily put a shotgun blast in his chest. There's always heroes come out in something like that, and that guy was."
An 11-year-old boy who was shot in the face and neck remained in critical condition Wednesday, according to officials at University Medical Center in Lubbock, Texas. A 13-year-old girl, Kendal Sanders, was listed as being in satisfactory condition with a gunshot wound to the arm.
The family of the injured boy has asked that his name not be released while he recovers.
The suspected shooter was transferred to an Albuquerque psychiatric hospital following a hearing Tuesday, according to attorney Robert Gorence, who is representing his family. Gorence said the family would release a statement Wednesday.