You really need to get quickly rid of those rats by any means necessary and don't worry about how humane any particular method may or may not be. As they multiply, their ratpopulation to food supply ratio will tip adversely to the point they will begin gnawing on anything they can find and that includes any plastic piping and electric wire insulation. Homes have been burned down and humans have perished in a most painful and inhumane manner because of it. Get some heavy duty spring rat traps for starters and if you have no indoor pets, some de con rat poison, but be aware the decon takes some time to work and the rat may crawl off in a search for water and die in a confined space resulting in an unpleasant odor inside your home.
Try to find how they are entering your home and block it off, tho once established, they may well just chew an new entrance way.
Believe me, the rats will have absolutely no moral misgivings about how much trouble they cause you or how physically painful their antics are to you. Tho I am doing so right this minute, the words Rat and Inhumane should never be used in the same sentence or context. Kill 'em--kill 'em all-- now!