SAO PAULO (AP) ― Part of the stadium that will host the 2014 World Cup opener collapsed Wednesday, killing two workers and aggravating already urgent concerns Brazil won’t be ready for soccer’s signature tournament.

The accident at the Arena Corinthians, known locally as the Itaquerao, could hardly have come at a worse time ― just a week ahead of the draw that will determine the tournament’s schedule and with the top names in soccer all descending on Brazil.

Preparations have been plagued by setbacks including cost overruns, stadium delays, accidents, labor strife and huge street protests in the run-up to the June tournament, once envisioned as a coming out party for South America’s largest nation, which is also scheduled to host the 2016 Olympics in Rio de Janeiro.

Already, public prosecutors and a workers union in Sao Paulo were demanding an investigation into conditions at the venue, saying work shouldn’t resume until authorities deem the stadium safe.

Ricardo Trade, CEO of the local World Cup organizing committee, said authorities would determine if there is a need to suspend construction.

“There are seven months till the World Cup, not 10 days, so I don’t believe this is going to cause delays. But there is absolutely no guarantee on this,” Trade said in a telephone interview.

The accident could lead to recriminations between local organizers and world soccer’s organization FIFA, which has set a December deadline for all 12 World Cup stadiums to be ready. The tournament begins June 12.

“I don’t want to know about FIFA right now; we are worried about the families of the victims,” said Andres Sanchez, former president of the Sao Paulo soccer club Corinthians, which is building the stadium. The club said workers will not return before a three-day mourning period.

The stadium was nearly finished before the collapse, which occurred when a construction crane crashed into a 500-ton metal structure. That structure then cut through the outer walls of the venue, destroying part of the outside of the building and slamming into a giant LED panel that runs across the stadium’s facade.