Security digicam footage broadcast by native media confirmed the carriages plunging in the direction of the bottom in the south of town.
“So far we have now 15 individuals who sadly misplaced their lives,” Mexico City Mayor Claudia Sheinbaum told reporters.
The city’s civil defense department said on Twitter that around 70 others were injured in the dramatic accident.
Emergency services were seen working to rescue victims from the carriages at the Olivos station.
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