Officials released a photo of at least one man wanted in the string of crimes.
The NYPD has confirmed at least 40 separate incidents since March.
The suspects get onboard like every other subway rider in New York. But unlike other riders, they have a key -- a key that unlocks one of the cabs where they pull the train's emergency brake.
And with that, they jump off the train and escape -- often into the subway tunnels.
"This is life or death stuff involving really complicated dangerous machinery that could endanger the lives of transit workers just doing their jobs and our customers, it's serious." MTA Chairman Patrick Foye said.
It's been happening mainly on the 2 and 5 lines.
Officials say it's been happening for several months and perhaps even since 2017. Not only does it put the train crew at risk because they have to get out and search the tracks, it also delays that train and every other train behind it.
Depending on the time and location when it happens, it can cause delays for thousands of people on multiple train lines.
Investigators are now going over footage from surveillance cameras, trying to put a stop to the false emergencies.
"It poses a danger and a risk to people anytime that you are disrupting," said NYPD Chief of Detectives Dermot Shea. "So we will investigate it accordingly and we will take it from there."
It all comes amid a series of assaults on riders and assaults on transit workers:
Police are seeking a man for allegedly attacking a female conductor on a B Train in Brooklyn and the man who brutally attacked a rider, who's identified only as a 22 year-old man from the Bronx.
And just Tuesday night, gunshots fired in the subway in Crown Heights left a tourist with a minor injury to her ankle.
Overall, major crime in the transit system is at its lowest levels in decades and on-time performance is up.
But now one transit watchdog believes that rampant farebeating could foster an atmosphere of lawlessness underground.
"Is there a sense of lawlessness that you can get away with things? People think that they can get away with evading the fare, what else can they get away with," MTA watchdog Lisa Daglian said.
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