What was going on? Turns out they were doing construction on the highway at night. Specifically, they were removing tiles from one of the highway's side walls by bashing with a bulldozer--how lucky for us. Let's just say by the time morning rolled around, the fellas ended up doing a great job.
Listen closely, you can hear the tiles crashing from our officetel (with our windows closed):
Look at the bulldozers...I'm guessing they are either made by Hyundai or Kia...
The morning after shot...ta-da!