The "G" line was extended by 5 stops in 2009, while repair work is done at the Culver Viaduct.
But when the project finishes, as soon as next year, the MTA could end the extended service.
"The neighborhoods in which the G stops have been extended are growing, are thriving, are vibrant, and to take that away is the most ridiculous thing you can do," said Brooklyn Borough President Marty Markowitz.
The MTA recently said no decision has been made yet on whether to keep the extra stops.
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