Security was heightened at Mattituck Junior-Senior High School Friday morning based on a situation that the school considers a possible threat.

News of the heightened security was posted on the school's Web site. Southold police say a 16-year-old student, who had been suspended for truancy, made unspecified threats to other students, teachers and staff members.

The school says the heightened security will last throughout the day and that students' backpacks may be searched. Students will also not be allowed to leave the campus Friday for lunch.

Police say they are talking with the teen. It is not clear if charges will be filed.

AP reports contributed to this story.