For a long period of time now, Russia is witnessing a very grave problem of sinkholes appearing every now and then and many expanding continually. Much of infrastructure has been disrupted, mines locked and many other activities at standby. Some small towns had to be completely evacuated to prevent any losses of lives.
For it has not taken in earth but rather spitted it out, like that in an explosion. No solid explanation is yet found for these occurrences but even if we do come up with one, are we be able to control it at all.