The McHenry County Sheriff’s Office is asking people to avoid the area around the Algonquin Dollar Tree at 1402 E. Algonquin Road.
The sheriff’s office said in a post on its Facebook page that there was a police presence at the store, and there is no threat to the public.
It was unclear what prompted the police response.
A McHenry County Sheriff’s Office spokeswoman said she didn’t have any information to share as of 4 p.m.
Check back for updates.