'Tough decision': Calgary Mayor Naheed Nenshi won't run for re-election this fall

Calgary Mayor Naheed Nenshi speaks after receiving an award from Prime Minister Justin Trudeau during the Public Policy Testimonial Dinner in Toronto on Thursday, April 20, 2017. Calgary Mayor Naheed Nenshi say he won't be running in the municipal election in the fall. THE CANADIAN PRESS/Christopher Katsarov