Brazil is threatening to halt construction on the already delayed World Cup stadium over concerns for workers' safety.
Prosecutors claim to have found irregularities at the Itaquerao Stadium, where nearly 20,000 temporary seats are being installed ready for the opening match in four weeks.
Constructors were reportedly advised about safety problems a few weeks ago, but nothing has been done.
But the company in charge of the temporary seats dismissed claims work would be stopped and said the complaints were about "minor issues."
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