The break-ins occurred at IXL Fitness on Route 9G between 4:45 p.m. and 6:15 p.m. on Friday, Nov. 4, police report.
The thief, or thieves, broke the windows in three locked cars and stolen valuables inside, according to police.
Police are asking anyone with information about the thefts to call Trooper Lisa Butenhoff at (845) 677-7300. All tips can remain confidential, police said.
They reminded the public not to store valuable items in cars.
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