Twenty three people have been killed after an overpass collapsed and caused a train to derail in Mexico City's metro.
An additional 49 people were rushed to hospital after the train was sent plunging downward onto a road, trapping cars under rubble on Monday night (local time).
Mexico City’s civil protection agency says about 70 people were injured.
“A support beam gave way,” Mexico City Mayor Claudia Sheinbaum said.
The incident unfolded about 10.30pm local time.
Video showed at least one broken train along with dozens of rescuers searching through the rubble of the collapsed overpass. Cars could be seen trapped underneath.
The accident happened on the metro’s Line 12, the construction of which has been plagued by complaints and accusations of irregularities.
Ms Sheinbaum tweeted that she was on the scene to help in the aftermath of the accident.
"Unfortunately there are dead and injured people. I am on site supporting the installation of the command centre," she said.
The city's Comprehensive Risk Management and Civil Protection Agency initially put the toll at 13 and 70 people injured.
The line was built when Mexican foreign minister Marcelo Ebrard was mayor of Mexico City.
"What happened today with the Metro is a terrible tragedy. My solidarity with the victims and their families," he said on Twitter.
"Of course, the causes must be investigated and responsibilities defined. I reiterate I am at the disposal of authorities to help in whatever is necessary."
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