Recently, I found some parts of the lawn and some areas quite near to the house itself were in a mess. I suspect that some animals like opossums may be the reason.
Are there any ways to keep them away from the lawn?
A picture would assist but wild animals are pretty consistent in one thing. They go where the food is. Is it possible your lawn has an infestation of white grubs? Skunks and crows will go after a lawn to eat the grubs but they make a mess doing it.
What part of the country do you live in and what season is it there?