It's unclear how they managed to access the cab on the train. MTA Chair and CEO Janno Lieber called the intrusion a "failure" of security that was "not acceptable," and suggested new train car models should lock up operator cabs using biometric sensors instead of traditional locks.

NEW YORK -- New York City police are searching for a group of people they say took a subway train on a joyride. The department released images and video Wednesday of six individuals who they say commandeered an unoccupied “R” train over the weekend.