A subway train derailed in Mexico City after an overpass partially collapsed onto a road Monday night, killing at least 23 people and wounding dozens of others.

Details: Mexico City Mayor Claudia Sheinbaum told reporters early Tuesday that children were among the dead, and 49 wounded people had been taken to hospitals.

• The crash happened at 10:25 p.m on Line 12 of the subway system, which opened in 2012, at the Olivos Station in the capital's southeast, according to La Jornada.
• Milenio TV broadcast footage showing the overpass collapsing onto cars on the road below it.
• Sheinbaum said a "support beam gave way," causing the overpass to collapse, AP reports.
• The rescue operation paused at midnight as workers brought in a crane to support the "very weak" train, per AP.

What they're saying: Foreign Minister Marcelo Ebrard, who was mayor of Mexico City when Line 12 was constructed, in a Twitter post called the crash a "tragedy" and said "the causes must be investigated and responsibilities defined."

The big picture: Mexico City's subway system is the second-biggest in the Americas after New York City, handling over 4 million passengers per day, according to the New York Times.

Editor's note: This article has been updated with new details throughout.