Police say 18 number 7 train windows were found broken at 61st Street-Woodside station in Queens.
Authorities have previously identified a person of interest.
The train was removed from service and the estimated cost to repair the windows is approximately $9,000.
Since April, there have been more than 70 incidents of smashed windows across four subway lines.
The MTA is offering a $10,000 reward for information that leads to an arrest.
"This criminal act means taxpayer money will be diverted from providing service, it unnecessarily delays riders, and puts an entire train into the repair yard," the MTA released in a statement. "We are cooperating with the NYPD which is aggressively investigating and the perpetrator, when arrested, will face both criminal prosecution and a demand for full restitution."
The MTA says the vandal or vandals have caused more than $300,000 in damage and numerous delays -- all at a time when the MTA doesn't have a dime to spare.
The $10,000 reward will be added to the NYPD Crime Stoppers' $2,500 reward for a total of $12,500.
MTA chief safety officer Pat Warren said one or more people are using weapons to smash out the windows on subway cars -- from inside the trains.
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"This takes considerable force," Warren said. "This has to be done with a blunt instrument of some kind. A hammer, a pipe, a baseball bat. Something significant."
So many windows have been broken that the MTA is running out of replacements. That will soon result in more time between trains - translating to longer waits on subway platforms and more crowded subway trains, two things MTA is actively trying to avoid during the pandemic.
"These vandals don't have the respect for our riders and those essential workers that depend on this service to get them back and forth to work," Warren said.
There are photos of the person police believe is responsible, but the attacks usually happen on empty cars, so there have not been any eyewitnesses. Police say if anyone recognizes the suspect, please give the cops a call because this crime is costly.
"This criminal act means taxpayer money will be diverted from providing service, it unnecessarily delays riders, and puts an entire train into the repair yard. We are cooperating with the NYPD which is aggressively investigating and the perpetrator, when arrested, will face both criminal prosecution and a demand for full restitution."
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