Two emails that each contain a threat to do harm at Half Hollow Hills High School East were being investigated by police Thursday, school and police officials said.
The threats -- one to district officials and one to Suffolk County police -- were sent Wednesday night, the school district said in a letter Thursday to parents in the district.
Officials said the threat sent to the district read, in part: "im gonna blow up hills east tmrw at 9 am . . . don't try to stop me; you will all die."
The district said the email to police read: "I am bombing Half Hollow Hills East Tomorrow at 9 pm sharpp."
Police said Thursday night they were investigating an additional threat directed at the school -- to happen Friday. Police would not comment further and no additional information about the latest threat was immediately available Thursday night.
Suffolk police confirmed receiving a threatening email on Wednesday.
"The school was searched and no suspicious items were located," police said in a statement, adding that the investigation is continuing.
The district said police investigators were at the Dix Hills building Thursday morning and that the department will "continue to provide guidance and assistance as they move forward with the investigation."
School officials said there has been "no recommendation" to evacuate the building but that, in "an abundance of caution," High School East and High School West will be closed to all students and visitors starting at 6 p.m.
All activities scheduled after 6 p.m. Thursday have been canceled, school officials said.
The district, in its correspondence to parents and guardians, asked them to speak with their children about "the severity and consequences" of making threats -- either verbally or in other forms, such as emails or digital postings.
"Students who are found to have made statements that threaten individuals or the school community," the email read, "will be subject to the maximum punishment allowable by law and the Half Hollow Hills Code of Conduct."