Here, in the big home improvement stores, Like Home Depot and Lowes, you can buy
Smoke bombs to kill moles.
They come in small round cartilages (3 to a pack). You light the wick at the end and throw it down into the tunnel.
Cover it up, quickly and go to the next hole. The CO-2 gas they emit kills them.
These resemble the road flares that are used if a car is pulled over because of some trouble,