Possible mole rat?

Since a few weeks I notice at two location on my lawn that there is a stroke where it feels as if there highness and loose soil where your feet sag.

On closer look I notice there are small heaps ( flakes ) of loose soil between the grass blades. There are no real heaps on top of the grass yet, but if you step on the grass the sand will be at the same level as the grass

There is no sign of death grass in those locations, it rather seems to be a bit healthier than other areas.

Before I start to dig, could this be a sign of a mole rat, and how to confirm and/or get rid of it?