An eighth-grader said he found a dead mouse inside a bag of Frito-Lay barbecue potato chips he bought in a school lunch line, and his claim appears credible, school officials said.

The boy reported he found the mouse Wednesday at Lewis-Palmer Middle School in Monument, about 40 miles south of Denver. The principal and a vice principal interviewed his parents and other students who were sitting at the same lunch table and decided the incident didn't appear to be a prank, said Donna Wood, a spokeswoman for the Lewis-Palmer School District.

Frito-Lay spokeswoman Aurora Gonzalez said Friday the Plano, Texas-based company expected to receive the bag of chips soon and will investigate to determine what action, if any, it will take.

"We take these things very seriously because we have stringent quality control in place," Gonzalez said.

Wood said the school district has temporarily pulled all chips from its vending machines and lunch lines.

Frito-Lay is a unit of PepsiCo Inc.