CHICAGO (CBS) — Thieves were in and out in less than two minutes in a high-end heist on the Magnificent Mile this weekend.

Around 7 a.m. Sunday, the thieves broke the glass at Na Hoku Jewelers, 600 N. Michigan Ave., and took the merchandise from inside, police said.

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An employee said the thieves used plywood to block the door – so as to make it look like the store was under construction.

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The thieves broke three cases and stole about 150 pieces of jewelry in a minute and a half, police said.

“This keeps on happening over and over again, and we feel like we need a little bit more protection – maybe another detective, or you know, maybe better cameras or police protection; presence,” said Carmen Imbrogno, district manager for Na Hoku Jewelers. This is the jewel of the city. Our Michigan Avenue is as good as it gets.”

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No one was in custody Sunday night in the burglary.