WAUKESHA COUNTY, Wis. (CBS 58) -- Waukesha County officials say a 70-year-old woman was arrested Monday, Dec. 1, after allegedly threatening staff at Richmond School in the Village of Lisbon. 

The woman allowed her dog to run onto school property just before 1 p.m., according to the sheriff's office, and some students attempted to catch it.

While retrieving the dog, the woman allegedly "made physical contact with two students and made threats directed toward school staff" before leaving the area.  

She was later arrested and taken to the Waukesha County Jail on charges of terroristic threats, intimidation of a witness, and disorderly conduct. 

The sheriff's office says additional patrols will be provided in the area as a precaution. An investigation is ongoing.