Rescue teams in Mexico City late Monday responded to the collapse of a metro overpass, killing at least 23 and injuring about 70, according to authorities.
The scene was chaotic. People posted images and videos on social media, which appeared to show the train cars inverted and resting on the road below. Authorities said cars were trapped. Dozens of rescue workers were at the scene.
At least one orange-and-yellow subway car was captured hanging from an overpass, which was about 16 feet above the road in southern Mexico City. A television host in Mexico City tweeted a video of rescue personnel using ladders to help passengers get down from a tilted subway car.
The city's Comprehensive Risk Management and Civil Protection Agency, in a preliminary number, said at least 13 people died and about 70 people were injured.
"What has happened on the metro today is a terrible tragedy," tweeted Mexican foreign minister Marcelo Ebrard.
The Associated Press reported that the accident happened on the metro's Line 12, the construction of which has been plagued by complaints and accusations of irregularities.
"A support beam gave way," said Mexico City Mayor Claudia Sheinbaum, who had rushed to the scene of the accident, which happened at about 10:30 p.m. local time.
Hundreds of police officers and firefighters cordoned off the scene as desperate friends and relatives of people believed to be on the trains gathered outside the security perimeter.
Sheinbaum said a motorist had been pulled alive from a car that was trapped on the roadway below. Dozens of rescuers continued searching through wreckage from the collapsed, preformed concrete structure.
"There are unfortunately children among the dead," Sheinbaum said, without specifying how many.
The Associated Press contributed to this report