SHELTON — The increased police presence in the area of Elizabeth Shelton School on Thursday was sparked by an incident Wednesday that left police searching for evidence, officials said.

The school’s principal, Bev Belden, sent out a message to parents through social media and the school district’s website around 11:45 a.m. Thursday about the police units in the area.

Belden said an incident happened late Wednesday night in one of the neighborhoods near the school.

“This morning, officers from the Shelton Police Department were checking areas near and around where the incident occurred to determine if anything was left behind,” Belden said. “Elizabeth Shelton School grounds was one such area. All the children are safe and student learning has not skipped a beat.”

Belden and Shelton Police Lt. Robert Kozlowsky said the incident did not happen on school property and that the school was never under any threat.