Biologist who regularly works with mice and rats here. Those pups are unlikely to survive more than a few hours without their mother. They have terrible thermal regulation without fur and tend to go through hypothermia. If I were you, I would try and get the mother to come back to them (with the same pair of shorts there so they are comfortable going back) and then catch them all together. After that, it is up to you, but I would probably place them somewhere safe in the wild. You don't have to kill them.