"Everybody OK here?" blares the speaker for Metro-North Railroad at Grand Central Terminal as surprised passersby wonder what happened.
Here's the drill: The train just hit the bumper at Grand Central. People were injured.
But it's just a drill. And all acting aside, the purpose of the exercise was really pretty simple.
It's "all about communication," explained Joseph Streany of Metro-North Public Safety.
The goal is to ensure the different agencies efficient work together in the case of a real emergency.
Still, for people in the terminal it was a little confusing.
Some wandered about asking what happened while others simply thought a public figure -- President Barack Obama, namely -- was in the building.
But an announcement echoing through the terminal tried to clear it up.
"Please do not be alarmed; this is only a drill," it blared.
The notification helped clear up some confusion.
"At first I didn’t know what was going on, then I heard the announcement that they were doing some drills," said Jenny T. who lives in san Francisco, Calif.
Saturday's excersise marks the 28th drill for Metro-North. Officials tell NBCNewYork many of the others have been terror-related and far more complicated. The most recent one was an effort to go back to the basics -- especially for the Metro-North employees posing as "victims."
"I’ve gotten my legs cut off, arms cut off," said Jeff Behm of Metro-North Operations, who played one of the victim roles, adding that he's "very resilient."
The LIRR conducted a similar training drill up in Sayville. And at Newark Liberty Airport, the Port Authority restricted media access as it partially shut down a terminal for a terror-training exercise.
Officials declined to comment about how the drill went.
As for the drill at Grand Central, the video will be reviewed and observers will be interviewed, so in the coming weeks officials will know how to make their emergency response procedures even more efficient and effective.