A fight between a bus driver and a passenger who missed her stop caused the bus to plunge off a high bridge into China's Yangtze River, police said Friday.
Rescuers lifted the wreck of the bus from the river Wednesday night.
A video retrieved from the black box of the bus shows a passenger scuffling with the driver just moments before the crash.
"Police said the passenger, identified as a 48-year-old woman with the surname Liu, was angry that the bus had missed her stop", the BBC reports.
During the fight, Ran lost control of the bus and the vehicle broke through a guardrail and plunged into the river with an estimated 15 passengers on board in Wanzhou, Chongqing.
Deadly road accidents are common in China, where traffic regulations are often flouted or go unenforced. When he refused, she walked up to the front of the bus to confront him.
As the quarrel escalated, the statement said, the woman hit the driver on the head with her cellphone.
The bus collided with an oncoming auto before smashing through barriers and into the Yangtze River on Sunday.
More than 70 rescue boats were deployed to the scene, reported China Daily.
The bus was travelling at a speed of 51 kmph (31 mph) at the time of the accident, police said, adding that the investigation has ruled out any mechanical failure as a cause of the accident.
The driver then took his right arm off the steering wheel as he tried to defend himself.
Authorities ultimately blamed the 42-year-old bus driver for not following safety protocols but found that both the passenger and the driver had broken the law and endangered public safety.