Parents turned out Tuesday to voice complaints to Oyster Bay school administrators after a janitor was arrested earlier in the week.
The janitor, Brian Hulsen, worked at James H. Vernon Elementary School.
He was accused of making terroristic threats.
Hulsen allegedly invoked the mass shooting at Columbine and told a teacher that he would shoot up the school.
Parents criticized school officials for not immediately communicating details of the arrest and the reason behind the lockdown.
Superintendent Laura Seinfeld apologized to the parents. She says that all of the locks at the building have been changed and that police have stepped up patrols at all schools in the district.
Hulsen has been suspended pending the outcome of the investigation and is banned from school property and having contact with any staff or students.