"It is sad because I knew them," Nancy Martinez, family friend, said. "It breaks my heart. I have two little ones."
The Dimmitt County Sheriff would not reveal much information, but fire officials said it appeared a father killed his 12-year-old daughter and 13-year-old son before setting the home on fire and killing himself.
Family friends identified the children as Andy and Adira Briseno.
"I just wish he would not do this. The kids were innocent kids," Martinez said.
Dozens of people wiped away tears and held each other up as they lit candles in memory of their young friends.
"It is really sad, really sad because the children, they're angles. This shouldn't have happened to them at all," Maria Aranda, neighbor, said.
"We're here for them and we're going to pray for them and we hope that everyone understands," Lori Ruiz, high school nurse, said.
The Texas Rangers are assisting with the investigation.
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