Vandals smashed the window of a menswear and school uniform shop in Spalding town centre over the weekend.
Mann and Son in Hall Place was targeted between Sunday night and Monday morning when the vandalism was reported to police.
Owner Nigel Mann said: “Someone attacked our window at some point over the weekend.
“But who it was, when it was and how it was done, I don’t know.”
Anyone with information should call 101, quoting incident number 67 of June 1.