Hmm, I can think of a bunch of ways to kill these rats, start up the ol' lawn mower and hook up a hose going into the hole from the exhaust use tin foil around a garden hose to fit it to the exhaust unless you have a less restrictive hose. If they do come out they will be drowsy and easy to step on/shoot. You can also make bucket traps really easy with a skinny tube like an arrow shaft and a pop can there are way more designs too if that doesn't work just go on YouTube and search mouse bucket traps. Fill the bucket with cooking oil instead of water though only fill it to where they can't touch the bottom
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