At least 99 people were injured when an Argentine commuter train slammed into the same Buenos Aires station where 51 people were killed in a similar crash last year.
Railway officials said the train failed to stop as it arrived at the Once station, crashing through the protective buffers and slamming into a retaining wall.
"Suddenly the train wasn't stopping. It came off the rails and crashed into the ceiling, which stopped it. Then an impressive cloud of smoke came out," hot-dog vendor Maxi Jaquet told the Associated Press.
"We ran and began to help."
Angry passengers quickly gathered and shouted "murderer, murderer!" at the injured driver before he was taken away by police and hospitalized.
Argentina's security chief Sergio Berni told local television that "there are no fatalities for now"and that five people had broken bones.
Jorge Ramirez, a chef who was on the train, told AP that the accident was "a tragedy".
"I saw people hurt, shouting, others thrown on the floor. The people in the first wagon ended up piled on top of each other," he said.
Buenos Aires has been plagued by rail accidents in recent years.
In addition to last February's deadly collision, there have been numerous incidents, including a serious collision in June of this year, when a speeding commuter train slammed into another train that had stopped between stations, killing three people and injuring more than 300.
Authorities said it was fortunate that, unlike the earlier major mishaps, Saturday's crash did not happen on a busy weekday, and that the train was only partially full.
Argentina has tried to ramp up oversight of its problem-plagued train system since last year's deadly train collision.
And, after June's deadly collision, officials put surveillance cameras in conductors' cabs.
The increased surveillance has already revealed some acts of negligence by railway personnel, officials said in July.
Transport Minister Florencio Randazzo said video images taken from the surveillance cameras showed drivers nodding off, on the phone or reading, sometimes with their hands off the controls altogether.
Agence France-Presse contributed to this report.