Crews were spotted shooting scenes around Millennium Park Sunday afternoon.
No sighting yet of the film's star, Mark Wahlberg.
Shooting is expected to wrap in early October.
Chicago again turned into 'Transformers' set
August 25, 2013 (CHICAGO)
Crews were spotted shooting scenes around Millennium Park Sunday afternoon.
No sighting yet of the film's star, Mark Wahlberg.
Shooting is expected to wrap in early October.
