Officials in Medicine Hat now say ridding the city of rats may now take up to two years.

The city has launched a new strategy using poison-laced hay bales to kill the vermin, set up in areas where rats have been spotted.

Snakes have also been let loose in the landfill to kill the furry pests.

More than 90 rats have been killed at the landfill since the first one was spotted.

Before the Norway rats showed up, Alberta had been free of the critters for more than fifty years.