"Suddenly [the bus rocked] and boom, boom … It flipped on to its side … It was very chaotic, and blood was everywhere," the male passenger of the citybus told reporters at the scene, as quoted by the South China Morning Post newspaper.
The bus was traveling fast at the time of the accident, the passenger stressed.
The incident occurred at 9 p.m local time (13:00 GMT).
While 14 passengers were able to leave the bus themselves, five remained trapped and had to be rescued, with one found dead, according to Wong Tai Sin Fire Station Commander Lee Kin-chung.
Among the 16 injured, seven people were rushed to the hospitals in a critical condition.
According to the newspaper, the bus rammed into concrete barriers that separate lanes on the driveway before flipping on to its side and mounting the pavement.
The police will investigate the reasons of the accident, special investigation officer-in-charge Cheng King-man told the newspaper.