If you saw a lot of police and emergency vehicles in the area around St. Gregory the Great School in Danbury today, don't be alarmed. Police, fire, EMS and other emergency services participated in "a full-scale exercise designed to prepare for the possibility of a mass-casualty exercise in the city of Danbury," according to a press release from the Danbury Police Department.

The exercise was planned by emergency managers from the city, in an effort to help protect residents so all departments would know exactly what to do in the event of an attack or emergency situation.

The drill took place today at St. Gregory's, as well as Broadview Middle School, Great Plain Elementary and Danbury Hospital. Dozens of emergency service workers and over 100 volunteer actors participated in the drill. The police department stressed that there was no reason for residents to be alarmed.