A Mexico City subway train overpass collapsed onto a busy road below on Monday night, killing at least 24 people, including children, authorities said. More than 60 people were injured.
Photos and video from the scene showed mangled train cars hanging from the crumbled overpass and rescue personnel searching and transporting the injured on stretchers.
“A support beam gave way,” Mexico City Mayor Claudia Sheinbaum said at the scene. She said the beam collapsed just as the train passed over it. The accident occurred on Line 12 near the Olivos station in the southeast of the city around 10:30 p.m. (11:30 p.m. ET).
The mayor, wearing a hard hat and face mask, told reporters at the site that 65 people had been taken to hospitals, and seven were in serious condition.
Mexico's civil protection agency later published an updated list of victims on Tuesday morning, showing that at least 79 people had been taken to area hospitals, including two 15-year-old females and a 17-year-old male.
Mexican flags across all government buildings were hoisted at half staff as a sign of mourning for the victims.
Sheinbaum earlier said that one of the victims was in a car under the collapsed overpass and was alive at a hospital. Rescue crews also recovered at least four bodies from the railway carriage, she said.
A crane was being used to hold up the train so rescue workers could continue to work, she said. Of the dead, some are children, Sheinbaum said without specifying a number.
Alfonso, a local resident, told NBC's sister network Telemundo that he had heard a screeching noise on Monday night. "I even thought that it was a car that had collided around here, but no, I came out and saw the scene," he said.
As Mexico's civil protection agency started sharing lists of the injured, friends and relatives of the missing waited for more news of their loved ones, but many feared the worst.
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Gisela del Ocaso, 43, told Telemundo she was looking for her husband, Miguel Angel Espinosa Flores, who was on board the train.
Del Ocaso got to the scene within 30 minutes of the collapse and had heard no news of her husband since. “I don't know what to do,” she said. “We are desperate. I have two children.”
Calls for an investigation amid safety questions
Sheinbaum confirmed on Tuesday that federal justice experts in Mexico who will be helping the city with an investigation to "discover exactly what happened and what the causes."
"My position is that we need to reach the truth," Sheinbaum said. "We need experts from the federal justice as well as an external and unbiased team to conduct the investigation and all the reports that need to be done and get to the truth." A Norwegian company will be in charge of the external investigation, she said.
Speaking at his regular news conference, Mexican President Andrés Manuel López Obrador said that the investigation should be done quickly and nothing hidden from the Mexican people.
The crash has raised questions about safety in one of the world's busiest metro systems. It spreads across a vast urban sprawl and is home to some 20 million people, transporting about 6 million people daily.
This marks the second serious accident at the Mexico City metro system this year after a fire broke out in the control center on Jan. 9 — killing one person, intoxicating dozens of workers, and knocking out service on several lines for weeks.
At least two additional grave incidents have been reported in areas around the capital since the metro system's inauguration 50 years ago. Two trains collided last year at the Tacubaya station, killing one and injuring 41 others. Another train collision in 2015 injured 12 people at the Oceanía station.
Line 12, where the latest crash took place, is one of the newest lines added to the Mexico City metro system. Its construction started in 2006 when Foreign Relations Secretary Marcelo Ebrard was Mexico City's mayor.
Allegations over design flaws and poor construction of the metro line surfaced shortly after Ebrard stepped down as mayor. The line had to be partially closed in 2013 and 2014 in order to repair the tracks, Telemundo reported.
"What happened today in the metro is a terrible tragedy. My solidarity with the victims and their families," Ebrard, who is considered a potential presidential candidate in the 2024 elections, tweeted on Monday.
"Of course we need to investigate cause and determine responsibility. I reiterate to all authorities my complete willingness to contribute to everything necessary," he wrote.
It's unclear whether the 7.1 earthquake that rocked Mexico in 2017 also caused damages that contributed to the collapse of Line 12.
Following the devastating quake, residents of the area surrounding the line reported seeing cracks and falling debris, particularly on columns connecting the Olivos and Nopalera stations, which had been previously closed for repairs. The section that connects the Olivos station to another nearby station, Tezonco, is the one that collapsed on Monday night.
In a press conference Tuesday morning, Sheinbaum said officials will be releasing a structural review performed last year on Line 12 as part of their continuous maintenance process.
At the time, no expert in charge of the review alerted anyone of any possible dangers, Sheinbaum said.
"If there had been any sinking point or anything like that, it would have been reported immediately," she said. "What happened here was a beam that fell in the area... . The cause of that fall is what we're trying to find out."