A Japanese climber on a descent from Mt.Futago in Saitama Prefecture was ambushed by an angry bear and used a flurry of hammer fist and front kicks to escape. While the attack may seem unprovoked, if you slow down the footage you can clearly see the cub @1:18 and it was most likely a case of a momma bear protecting her young. Thankfully the climber did enough to scare it away and had a sense of humor about it joking about his martial arts background:
“Looking back at the video, it seems that the bear attacked me to protect the cub. I invaded bear territory, but since they attacked me, I defended myself with self-defense. I learned karate when I was a child, but I liked mixed martial arts now, so maybe I could use hammer fist instead of punches.”