Portland police continue to investigate threats against three area high schools, after they provided extra security at the schools Monday morning.
But police spokesman Pete Simpson says officers now "believe the threats to students are not credible."
The principals at Jefferson and Madison high schools sent messages out Monday afternoon calling the investigation a "serious matter.” They asked students with information to come forward.
Students at the two public high schools, and at De La Salle North Catholic, reported receiving violent threats over the weekend.
School officials alerted parents and staff of the threat Sunday night.
The messages to the Jefferson and Madison communities Sunday night said students had received "anonymous calls from an individual claiming that they were going to bring a weapon to both campuses Monday morning."
De La Salle North Catholic Principal Tim Joy informed his parents that students at the small private school received similar threats.
Police showed up at the three Portland area high schools Monday as a precaution.
Portland Public Schools spokeswoman Christine Miles said there was nothing unusual at Madison and Jefferson schools, although attendance appeared to be somewhat lower than usual.
De La Salle North Catholic involves a work internship for students — meaning about a quarter of the student body is off-site on any given day. Principal Joy said many students went straight to their work assignment Monday, rather than doing their customary check-in at school.
In their messages, the Jefferson and Madison principals applauded students for alerting police to the threats of campus violence.
Dear Families, As you’re aware Portland Police have been investigating threats of violence at our school and they tell us today the threats are not credible. The same threatening message to bring a weapon to Madison and Jefferson high schools has also gone to students who attend De La Salle North Catholic High School.
The investigation is a serious matter and police continue to investigate the source of the anonymous caller. We take threats of violence at our school seriously and they will not be tolerated. We will continue to work with police until this matter is resolved.
We are still asking students with any information regarding the calls to talk with a teacher, administrator or school resource officer. We all play a role in keeping our schools and communities safe.
The messages were signed by principal Margaret Calvert (for the Jefferson community) or Petra Callin (for the Madison community).
Statements sent to De La Salle North Catholic High School parents were not immediately available.