It is not clear from the OP (and the linked press article is in Thai) whether the old person crossing the road was killed, or whether it was the motorcyclist who hit the back of the bus.
I'm guessing that a 50 year old delivery motorcyclist (Pornsak) died when colliding with the back of a bus which stopped quickly due to an MG swerving to avoid an unnamed old person who stepped into the road under a pedestrian bridge.
But anything is possible.