Rescuers were struggling to comb through the wreckage of the Aldi store in Bad Homburg, near Frankfurt, because parts of the building remained at risk of collapse.
"It can't be ruled out that more people are (trapped) in that area," a police spokesman said. Two of the injured were reported to be in serious condition.
The crane fell onto the checkout area of the supermarket shortly before noon. It was on a construction site next door.
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