At least 49 people have been killed and 600 others injured after a packed commuter train ran into the buffers at a railway terminus in central Buenos Aires during the morning rush hour.
The train was packed with morning commuters when it entered the busy Once station at 26 km/h and crashed into barriers.
Officials said the train was unable to stop, possibly due to faulty brakes, and it crashed into the buffers inside the centrally located Once station.
More than 800 passengers were aboard the train, state news agency Telam reported.
A police spokesman said 49 people had been killed.
"The train entered the Once station at 26km/h,” Argentine transport secretary Juan Pablo Schiavi said. “We suppose there was some flaw in the brakes."
The trains are usually packed with people standing between the seats, and many were thrown into each other and to the floor by the force of the hard stop. Survivors told a TV channel that many people were injured in a jumble of metal and glass. Passengers said windows exploded as the tops of train cars separated from their floors.
More than 30 people were still trapped in the wreckage three hours after the crash.
Video broadcast by Buenos Aires television channels showed emergency workers rescuing injured passengers after cutting the roof off a carriage, while helicopters and ambulances took others to hospital. Workers also lifted the injured, tightly packed inside carriages, from the wreckage through windows.
Hundreds of thousands of people travel into Argentina's capital from the suburbs every day. The dilapidated and overcrowded rail services, run by private companies and heavily subsidised by the state, are plagued by crashes and delays.
In September, two commuter trains crashed into a city bus, killing 11 people. And one year ago, four people died during another train crash.
Agencies