The Imam and Shaykh Muhammad Ibn Saalih al-Uthaymeen (may Allah have mercy upon him) stated:

When you want to kill a rat, and killing it is recommended, do well in killing it. Kill it with that which will cause its soul to leave right on the spot. Do not harm it. From the ways of harming it is that which some people do when they put something down to catch it by way of sticking it (ex. using glue or a mouse trap). The rat is stuck to it (i.e. the trap); then the person leaves the rat to die from hunger and thirst. Continue reading →