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.

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

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.”

No one was in custody Sunday night in the burglary.