The incident occurred on Monday, Nov. 13, in Huntington Station at the Saks Fifth Avenue store on Walt Whitman Road.
Police said the man attempted to steal the clothing and was stopped by a store employee whom he threatened with a knife.
The man then dropped the clothing and fled in a black Nissan Sentra, police said.
Suffolk County Crime Stoppers offers a cash reward for information that leads to an arrest.
Anyone with information can contact Suffolk County Crime Stoppers by calling 1-800-220-TIPS, or online at www.P3Tips.com.
All calls and emails will be kept confidential.
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