SAO PAULO (AP) - World soccer governing body FIFA said it was assessing the extent of damage to the stadium hosting the 2014 World Cup opener as officials inspected the grounds Thursday to determine what may have caused the deadly accident, just weeks before all stadiums for one of the biggest events in world sports were scheduled to be completed.
Two workers were killed Wednesday when a crane collapsed and a 500-ton metal structure toppled over part of the stadium in Sao Paulo, aggravating already urgent worries that Brazil won't be ready for soccer's showcase event next year.
FIFA wants all 12 World Cup stadiums ready by the end of December, and Brazilian news reports have cited unnamed workers as blaming the rush to finish the Arena Corinthians for the decision to raise the last missing piece of roofing on Wednesday, despite several days of heavy rains that softened the earth around the stadium.
The hypothesis that the rain-soaked ground might have ceded under the weight of the equipment is one of three main lines of investigation, said Brazilian media reports. Human error and a problem with the crane are the other hypotheses.
In the wake of Wednesday's accident, it looked increasingly likely that FIFA will have no choice but to accept the Sao Paulo venue after its original December deadline. Brazilian officials have halted work on the stadium at least until Monday, and could decide to freeze further work for weeks or even months. Such a decision would come as a blow to FIFA since the governing body has said repeatedly stressed it has no Plan B for next year's World Cup - particularly since nearly 1 million tickets to the matches have already been sold.
''It is too premature to make any detailed assessment on the situation of the Corinthians Arena as we are still awaiting the technical report to be able to evaluate the scale of the damage,'' FIFA said in a statement sent to The Associated Press. ''We will be able to provide an update earliest next week following the FIFA Organizing Committee of the FIFA World Cup.''
The accident comes days ahead of next week's high-profile World Cup draw in the resort city of Costa do Sauipe to be attended by FIFA officials and other top names in world soccer.
Work at the Corinthians Arena was advanced but all activities have been halted at least until Monday to give workers a three-day mourning period. Workers who showed up at the site on Thursday were turned back by security guards.
Load operator Sergio Almeida told the AP he believed the crane operator might not have followed proper procedures.
''The crane operator moved the piece about 50 meters and then left for lunch. Someone must have told him to do that because you aren't supposed to move the crane with the piece on it,'' said 23-year-old Almeida. ''It was the last one. But it kept swinging. He tried to right it, but when he saw what was going to happen, he jumped.''
A sequence of photos released by the sports daily Lance showed the metal structure going down and the crane falling just moments later after not sustaining the weight.
Constructor Odebrecht said it would not immediately comment on unsourced reports by local media saying that there had been a previous warning about the stability of the ground underneath the crane. Odebrecht has said the model of the crane is one of the most advanced in the world and can sustain loads three times heavier than the metal structure that it was carrying.
Besides the Corinthians stadium, Odebrecht is also involved in the construction of the new Fonte Nova stadium in Salvador and the Arena Pernambuco in Recife. It also renovated Rio de Janeiro's Maracana Stadium, home of the final.
Former Corinthians President Andres Sanchez said Wednesday that the accident didn't cause any major structural damage, but added that getting the stadium delivered on time was the least of the club's concern.
''I don't want to know about FIFA right now; we are worried about the families of the victims,'' he said.
Ricardo Trade, CEO of the local World Cup organizing committee, said only local authorities would determine if there is a need to suspend construction, but he didn't ''believe this is going to cause delays'' with the World Cup opener nearly seven months away on June 12.
FIFA released a statement on Wednesday saying that ''the safety of workers is the top priority'' for football's governing body.
The stadium was about 94 percent finished before Wednesday's accident. The metal structure that collapsed cut through the stadium's outer walls, destroying part of the outside of the building and slamming into a giant LED panel that runs across the facade.
The newspaper Estado de S. Paulo said public prosecutors had previously pointed to 50 irregularities at the venue, including some related to emergency drills.
World Cup 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.
Wednesday's weren't the first fatalities at 2014 World Cup stadiums. Three workers have died in accidents at three construction sites over the past two years, and one stadium had work halted for nearly a week this year because of safety concerns.
The web portal R7 reported Thursday that 23 construction workers were killed in on-site accidents and another 132 were injured over the past five years in the city of Sao Paulo alone. The report said it had compiled statistics from the municipal health ministry.
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