65 more were injured in the blasts, he said.
Two of the bombs exploded near buildings under construction that were used as observation positions by security forces, while the third struck the entrance to a market.
The bombings come as Iraqi federal and Kurdish security forces battle a jihadist-led militant offencive that was launched in June and has overrun large areas of five provinces.
In the early days of the onslaught, Iraqi soldiers left their positions in oil-rich Kirkuk province, the capital of which is the city of the same name.