Update 1:00 with comments from St. Louis Mayor Francis Slay.
A design, engineering, architecture and construction firm is moving its corporate headquarters from St. Louis to Chicago.
Chicago Mayor Rahm Emanuel's office says Clayco's decision to relocate its headquarters will create about 300 new jobs in Chicago in the next few years. Clayco already has 280 employees in the Chicago area. The company plans to keep its office in St. Louis and no layoffs are planned.