The injured are residents of the Kahatagasdigiliya area, aged between 35 and 48 years. The driver of the bus was also among those injured in the accident.
Police said the group had been returning home to Kahatagasdigiliya after completing a pilgrimage to Kataragama when the accident occurred.
At the time of the incident, around 30 passengers, including women, were travelling on the bus, police added.
The injured were admitted to the Thammennawa Base Hospital and the Anuradhapura Teaching Hospital for treatment.
