Peekskill High's June 23 graduation will be held at the Paramount Theater instead of the traditional location on a school field, Superintendent James Willis said.
Police Chief Eric Johansen said the threat was discovered and reported in March.
"Our detective unit immediately performed an investigation, deemed the threat credible and arrested a 17-year old male student," he said.
The boy has been charged with making terroristic threats and is free on bail, said Bob Knight, a spokesman for the city, about 40 miles north of New York City. The student's name has not been made public.
The nature of the threat wasn't disclosed. Willis said in a letter on the district website that it was "aimed at the graduation ceremonies." Knight said it was "made toward multiple other students."
The police chief said the student was "expelled for the remainder of the year."
"Although there have been no further threats since March, we have decided to move graduation" to the theater, the chief said. He called the Paramount "a more secure location."
The superintendent said, "We all recognize the longstanding history of the outdoor high school location for graduation, but in today's society, we also know that taking precautionary steps to ensure safety is the wise thing."
The following letter was sent to teachers and parents:
Dear Students and Parents:
We are changing the location of our high school graduation.
We had received a credible threat aimed at the graduation ceremonies and that threat has been addressed by the Peekskill City Police Department. Several discussions have been held between the Superintendent, the Board of Education, the Chief of Police, the District's head of security and city police. Based upon the recommendation of the police and after great deliberations, the decision has been made to move the graduation site from the high school parade field to the Paramount Theater.
This move is one of precaution and safety. We have every confidence in our security staff and the Peekskill city police that these wonderful graduation ceremonies will take place without incident. We all recognize the longstanding history of the outdoor high school location for graduation, but in today's society, we also know that taking precautionary steps to ensure safety is the wise thing.
We will be posting many details on the website and elsewhere about the graduation ceremonies and we encourage you to contact the high school if you have any questions. Our focus is to provide the safety and security that allows our graduating students and their families to cherish this once-in-a-lifetime event.
Superintendent of Schools
Each student will still receive four tickets for admission to the ceremony. Those that do not need four tickets will be able to return their extra tickets so that students with a larger number of guests can be accommodated. Seating will be on a first come-first seated basis. There will be additional security measures taken upon each individual's entry to the theatre. Please arrive in time to be seated prior to the ceremony's start. Doors open at 1:00 p.m. and the ceremony will begin at 2:00 p.m.