CLARK FORK — Clark Fork Junior/Senior High School went into lock-down mode for about two hours Tuesday after a threat was apparently made against a teacher over a bad grade.

School officials were advised of the alleged threat by operators of a national toll-free hotline students are encouraged to call if they become of aware of threats or weapons in schools.

Bonner County Sheriff’s officials said the anonymous caller reported overhearing a conversation wherein a student made threats about injuring a teacher because of a bad grade. The teacher’s name was not disclosed on Wednesday.

“We’ve contacted that teacher and talked about different students. The teacher’s aware of what’s going on so they’re taking the appropriate precautions,” said Lt. Doug Harris.

The school was locked down from about 11:25 a.m. to about 1:20 p.m. while deputies investigated the incident.

Nobody has claimed responsibility for calling the hotline, which is impeding efforts to identify the student who allegedly made the threats.

“It’s really difficult because the person that made the call is unidentified,” Harris said, adding that the caller might not even be a student at the school.

Harris said detectives received some additional information late Tuesday night and again on Wednesday.

“We’re just trying to gather all the loose ends,” he said.

The 1-866-SPEAK-UP campaign launched in 2002 based on statistics which show that in the vast majority of incidences of school violence, attackers told other students about their plans beforehand.

Lake Pend Oreille School District Superintendent Dick Cvitanich could not be reached Wednesday and did not return a call seeking comment.