Video of the incident released Friday appears to show a passenger striking the driver in the face, prompting him to hit back before veering into oncoming traffic and barreling through barriers on the side of the bridge.
Surveillance footage showed the bus veered across the lanes, hit a auto, demolished a section of Yangtze River No 2 bridge's barrier and plunged into the river, where the water is about 70 metres [230 feet] deep.
China's state-run media released footage recovered from a CCTV camera present on the bus.
China's Ministry of Emergency Management said the local fire service had deployed 50 firefighters, five fire engines and two rescue boats to the scene, according to the South China Morning Post. This made the woman angry, so she advanced to the front of the bus and began yelling at him.
The official Xinhua News Agency said 13 bodies have been retrieved from the river and two others remain missing.
As the quarrel escalated the woman hit the driver on the head with her smartphone, the statement added.
The driver, whose left hand was on the steering wheel all the time, used his right hand to turn the bus, taking the vehicle, at a speed of 51kph, into the opposite lane.
Rescue workers and boats on the site where a public bus plunged into the Yangtze River after colliding with a vehicle in Chongqing, China on Oct 28, 2018.
The statement concluded that both the passenger and the driver had broken laws for seriously endangering public safety.