Two young girls walked away from their school Thursday without anyone realizing they had left, according to officials.

Chiana Rivera, 4, and Vanessa Herrera, 5, walked out of Loya Primary School Thursday afternoon and headed down Herring Road.

"You don't expect that to happen when you're thinking they're gonna be at school... and you get a call saying your kid walked out of school, " said Mayra Rivera, of San Elizario.

"What I can't believe is that a 4-and 5-year-old walked out of the school and nobody saw them leave. They're supposed to keep their eyes on them at all times," said Anna Herrera, of San Elizario.

Neither mother was informed about what happened until their daughters had been found.

"They told us it was 10 minutes, but it couldn't have been because they walked a long distance and they had time to cross that dangerous street," said Herrera.

After walking out of the school, the girls crossed the busy intersection at Socorro and Herring Road. They walked nearly one mile before being spotted by a school bus driver who alerted the school. District administrators are not aware of something like this ever happening before.

"On campus at Loya, we have not heard of similar incidents, at least since our superintendent has been here, and he's been here for about 12 years," said Cynthia Marentes, of San Elizario Independent School District.

Students pair up when they're going somewhere inside the school, but some argued that it isn't good enough.

"They have the buddy program where they send two students, one that was just there and the other one that takes 'em, walks 'em to class. That's the system that they have. Obviously, it's not working," said Rivera.

However, district officials concede there's no perfect solution to prevent this from happening again.

"Incidents will happen like this, but it is our priority to stop them and to prevent them, and not to have them become a regular thing in our campus," said Marentes.

The district will remind staff of the necessary procedures and encourage them to keep a better eye on students who are moving through the hallways.