LAFAYETTE, Colo. — Lafayette Police and the Boulder Valley School District are investigating an incident in which two special needs students were left behind on a school field trip.

The Centaurus High School sophomores were on a nature walk with classmates last Thursday when they became disconnected from the group.

“You know when I heard about it, I just got sick to my stomach,” said Jessica Douglas, the mother of one of the students. “I mean I’m thankful that he’s okay but… he could have ended up killed.”

Douglas’ 16-year-old son, Tanner Bergner, has the mentality of a 5-year-old.

Because he has no sense of stranger danger and no sense of direction, he requires constant supervision. His mother is upset that a teacher and two paraprofessionals cut short the search for the boys at Waneka Lake Park before finding them.

“They should have stayed at the lake until police arrived,” she said. “They should have never stopped looking for him.”

A jogger at the park saw the students and ended up delivering them to police.

In a statement Monday, the Boulder Valley School District said it takes the incident “very seriously, we’re very concerned. Kids  should not be unsupervised, particularly special needs children.”

The three school employees are now on administrative leave.