The woman purchased a Louis Vuitton bag at the Walt Whitman Shops on Friday, Jan. 28, according to Suffolk County Crime Stoppers.
After leaving the store, the woman saw another woman filming her, authorities said.
The woman then returned to her home in Deer Park, parked her car and entered the residence, Crime Stoppers reported.
A man was then seen exiting a gold Honda Odyssey from the passenger side, authorities reported.
He walked up to the woman's car, smashed the window and stole her purse, authorities said.
The man was then picked up by the driver of the Honda and fled the scene, Crime Stoppers reported.
Crime Stoppers is offering a cash reward for information that leads to an arrest.
Tips can be submitted by calling 1-800-220-TIPS.
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