Cherry Creek School District officials temporarily implemented “secure perimeter” protocols at three elementary schools in Greenwood Village on Thursday morning due to police activity outside.

High Plains Elementary, Cherry Creek Academy, and Cottonwood Creek Elementary schools had those protective protocols in place. It wasn’t immediately apparent to school officials why police were visible in the area in south metro Denver.

“’Secure perimeters’ means they cannot have any students outside. And no one can come into the school buildings,” school district spokeswoman Lauren Snell said.

“We don’t want anything with the police, the activity outside, to come into our schools.”

The status was lifted at the three elementaries as of 9:14 a.m.