Wrigley Field is site of active-shooter drill

(Clarice Barbato-Dunn/Flickr)

Chicago first responders are planning to simulate a large-scale active shooter incident at Wrigley Field.

Thursday's emergency response exercise will run from 7 a.m. to 2 p.m. and include Chicago fire fighters and police officers, the city's emergency office and the Chicago Cubs. Chicago police say the drill was planned months ago to coincide with Major League Baseball's All-Star break this week. Cubs spokesman Julian Green says the team is happy to partner with law enforcement on the exercise to ensure a safe and secure environment.

Officials warn the public that the drill will include "simulated ammunition and flash bangs." Chicago police have held similar drills at other large venues.

Sections of roadways around the ballpark will be closed to vehicle and pedestrian traffic while the drill is taking place.