Local sources said the incident happened after 10 p.m. local time (4 a.m. KST). Members of the public in the area assisted police and rescue teams in the rescue efforts.
Videos posted to Twitter show crowds of people watching rescue teams scramble to help the injured.
Two wagons can be seen suspended above the rubble of the collapsed structure.
A man participating in the rescue effort is pictured using an extension ladder to reach the window of one of the cars.
Moments later, she arrived and described the sight of firefighters and medical personnel.
She added that several hospitals were taking care of the injured and that there had been deaths.
The message said at least 13 people died in the crash, while around 70 others were injured.
The tweet added that people were being taken to various hospitals, including Magdalena de las Salinas and Belisario Domínguez.