Search and rescue efforts for survivors continued into the night.
At least 18 people were killed and nine injured on Friday when a passenger bus veered off a bridge and plunged into a streambed in El Harrach, east of Algiers, Algeria's Civil Protection agency said.
The accident occurred at around 5:45 p.m. (1645 GMT), the agency said.
Two of the injured were in critical condition.
Victims were taken to a local hospital, while the bodies of the dead were transferred to a morgue.
Civil Protection deployed 25 ambulances, 16 divers, and four semi-rigid boats to the scene.
Videos on social media showed civilians wading into the water to pull victims from the partially submerged bus before rescue teams arrived.
Officials warned the death toll could rise as recovery operations continued.
Algeria records up to 4,000 road deaths annually, official data shows.
The National Agency for Road Safety attributes 91 percent of accidents to human error, particularly driver fatigue and failure to obey traffic laws.
Poor road and vehicle conditions, along with environmental factors, also contribute.
