Cape Hedo Midnight Shouting

It happened to us for a month ago, but I was shocked to post it right away. My wife and I were camping with a yellow camper van on the island and spent a peaceful (or so thought) night on the 8th of October in the parking lot at Cape Hedo. The October night was surprisingly warm, a nice breeze filled the air, and we prepared ourselves for the night. We opened up the tent on the roof of the camper van in the empty parking lot and went to sleep. We already slept at other place in Okinawa, without any problem. Sometime after midnight, my wife was waking me up terrified. In the otherwise empty parking lot, one guy was standing 50 meters away from our car and started to shout at us. Some words in English, then in Japanese. He seemed to be pretty angry, and the way he was shouting was terrifying. We couldn't see his face, because it was a pitch black night. Some words we got out from what he was shouting were "you came here", "you did it". Some moments later, he disappeared for a couple of minutes and went to the east lookout. He came back a couple of minutes later to the spot where he stood before. He stayed there for a while. Then he turned straight to our car and started approaching it in a straight, self-conscious manner. We still couldn't see his face, but it was very terrifying.
On his midway, I shouted at him to stop right there, otherwise I am calling the police.
He was surprised and started to explain that he is afraid… (altough he scared the shit out of us) and his ride to Cape Hedo took so long. He didn't explain himself, nor did he calm down. He just said, he will be gone, and we will not hear from him anymore… Then hi picked up a bike from a shadowy place and drove off.

Since then, we couldn't really put together, what was just happening there.