A Connecticut elementary school is canceling its Halloween parade and banning students from wearing costumes in school this year.

The principal of Lillie B. Haynes in Niantic sent a letter to families on Wednesday with the decision and said school leaders made the decision with input from staff members.

“This decision was based on many factors including safety and exclusion of students," Principal Melissa DeLoreto said in a statement. "With increasing societal safety concerns, the number of adults who attend this event, some in costumes, poses a potential safety threat.”

School officials said students in past years have been excluded from participating because of religion and cultural beliefs.

“We believe school day activities must be inclusive for all students and we must be sensitive in regards to holidays and celebrations of religious, cultural or secular nature,” DeLoreto wrote. “Please know classroom celebrations will continue to take place however, they will be Fall themed, not Halloween.”

DeLoreto said classroom teachers will send home information about the celebration.

"I think it's a little overreaction -- knee jerk," said parent Shawn Prevost, whose two nieces and a nephew attend the school with his daughter. "But it's one thing that happens. As parents you have to explain to them the reasons behind it."

But another parent noted that there are other ways to celebrate Halloween in town, including at East Lyme's "Trick or Trunk" event.

NBC Connecticut also reached out to the superintendent, but has not heard back.