A bus plunged into a ravine killing three passengers in Indonesia.

The Ketty inter-provincial bus was driving along the Toraja-Kendari route when it careened off the mountain road with no guardrails in South Sulawesi province at around 11 am local time today, December 3.

Footage shows rescuers carrying injured passengers up the muddy slope as officers searched the overturned vehicle for more survivors.

AKP Ahmad S., Head of Criminal Investigation Unit of the Palopo Police, said: 'Yes, that's right, the Ketty bus accident happened at kilometer 14 Battang. The Traffic Unit is already at the scene.'

There were nine people - six passengers and three crew - onboard the bus during the accident. Two passengers were declared dead at the Pallamai Hospital, and one more died at the Sawerigading Regional Hospital. The injured individuals were being treated.

Authorities were investigating the cause of the accident.

Road accidents are common in Indonesia due to substandard infrastructure, poor road safety education, and widespread traffic violations uch as reckless driving and lack of helmet use among motorcyclists. High vehicle density and insufficient law enforcement also exacerbate the problem.