UVALDE, TEXAS - For Irma Garcia and Eva Mireles, teaching fourth graders at Robb Elementary in Uvalde, Texas, was one of the joys of their lives, a vocation dedicated to educating children and keeping them out of harm's way.

Relatives briefed by police said Garcia and Mireles died on Tuesday (May 24) trying to protect their students after a gunman burst into their classroom, barricaded the doors and opened fire with a semi-automatic rifle.

Nineteen children, aged nine and 10, and the gunman himself were killed, and multiple others were wounded.

Garcia, a married mother of four who taught at Robb Elementary for 23 years, was a "sweet, kind, loving" teacher who considered her students to be family, her relatives aid.

"She passed away with children in her arms trying to protect them," her nephew John Martinez wrote on Twitter. "Those weren't just her students they were her kids as well."

The daughter of the other teacher, Eva Mireles, penned a tribute to her mother on Wednesday, which was to have been nearly the last day of the school year.

"I don't know how to do this life without you, but I will take care of dad. I will take care of our dogs and I will forever say your name so you are always remembered, Eva Mireles, 4th grade teacher at Robb Elementary who selflessly jumped in front of her students to save their lives," Adalynn Ruiz wrote on Facebook.

Garcia, 46, was named "teacher of the year" at the school to which she dedicated her entire career. In 2019, she was one of 19 San Antonio-area educators named as finalists for Trinity University's prize for excellence in teaching. At the time she taught third grade, specialising in social studies and ELAR, or English Language Arts and Reading.

"I am so excited to begin this new school year already!" Garcia wrote in note on the school district's website before this academic year began.

Nevaeh Bravo
Amerie Garza
Irma Garcia
Eva Mireles
Uziyah Garcia
Ellie Garcia
Xavier Lopez
Maite Rodriguez
Makenna Elrod
Tess Mata
Annabelle Rodriguez
Rogelio Torres
Alithia Ramirez
Jayce Luevanos
Jailah Silguero
Miranda Mathis
Elijah Torres

Descansa en paz. ❤️ pic.twitter.com/mhexb150Yc

— Gabe Gonzalez (@ALatinxHorror) May 25, 2022

The longtime educator offered students a glimpse into her personal life and her passions, saying she loved barbecuing with her husband of 24 years, Joe. She was the proud mother of four: her eldest son was at military boot camp and her second son at Texas State University. She had two younger daughters as well.

A Facebook photo showed her husband and son holding a heart-shaped sign that reads "Proud Bobcat family," a nod to the football team at Texas State.

Eva Mireles was trained in bilingual and special education.

She loved outdoors activity like running and hiking and cherished her husband, daughter and "three furry friends," according to a short biography pasted on the school's website.

Her husband, Ruben Ruiz, is a police officer on the school district's police force, the agency investigating the massacre.

Her aunt, Lydia Martinez Delgado, grieved for her niece in a Facebook post, asking for prayers for her family and the entire town of Uvalde.

The community, about 130km west of San Antonio, has about 16,000 residents, nearly 80 per cent of them Hispanic or Latino, according to US Census data.

"I'm furious that these shootings continue. These children are innocent. Rifles should not be easily available to all. This is my hometown, a small community of less than 20,000. I never imagined this would happen to especially loved ones," Martinez Delgado said in a statement.

"All we can do is pray hard for our country, state, schools, and especially the families of all," the statement said.

There were two days left in the school year when Tuesday's massacre unfolded. The school district cancelled classes for the remainder of the school year and has established grief counselling for the survivors.