SAO PAULO, Brazil -- Brazilian police plan to talk Friday to the operator of the crane that collapsed this week and killed two workers at a stadium set to host the 2014 World Cup soccer tournament opener. Police said they hope the interview will help investigators pinpoint the cause of the accident, which has cast more doubt on Brazil's preparedness for hosting the showcase event.
A police inspector told The Associated Press on Friday the crane operator is not yet suspected of any wrongdoing but is considered a key witness to Wednesday's accident at the Arena Corinthians.
"We can't say anything about responsibility yet, but he was right there where the accident happened and it will be extremely important to hear what he has to say," inspector Luiz Antonio da Cruz said in a telephone interview.
Meanwhile, inspections continued at the construction site on Friday, and with crews analyzing options to restart work in the area where the crane collapsed while trying to hoist a 500-ton metal roofing structure.
The piece crashed down damaging part of the stadium and raising fears that the facility may not be ready in time for the June 12 World Cup opener. Delays caused by the accident will almost certainly keep Brazil from delivering the remaining six World Cup stadiums by the end of the year as required by world's football governing body FIFA.
Local organizers say the stadiums will be ready, but FIFA is waiting to find out the extent of the damage before guaranteeing Sao Paulo will remain the opener host. An announcement from FIFA isn't expected until next week just before the high-profile World Cup draw in the resort city of Costa do Sauipe.
Inspector Cruz said the crane operator will likely reveal the most about the accident. His name was not being released out of fear that other workers could make an attempt on his life, Cruz said.
"We have to know what he saw, what he knows," Cruz said.
According to witnesses, the crane operator jumped out of the machine when he realized it was collapsing with the 500-ton metal roofing structure still attached to it.
Brazilian media reported he was in shock after the accident and was allowed to go home. Cruz said police so far have only made an informal request to talk to him. The interview was expected to happen Friday, but it could also be pushed back to next week.
Civil defence authorities said Thursday they were following three lines of investigation -- human error, mechanical problems or instability with the ground underneath the crane.
A safety engineer allegedly warned his supervisor of possible problems with soil firmness around the stadium due to recent rains but managers brushed aside his concerns, a labour union leader charged Thursday. Odebrecht, the powerful Brazilian construction company behind the Corinthians stadium project and three other World Cup venues, strongly denied the accusation.
Cruz said he also talked to the engineer in charge of the crane operation at the time of the accident, who denied any wrongdoing.
"He said that they had conducted similar operations several times before at the site and nothing had gone wrong," the inspector said.
Civil defence officials said Thursday that work can resume on most of the stadium after a three-day mourning period ends Monday, but the Labor Ministry said Odebrecht was prohibited from using the other nine cranes at the site until they can show "safety measures are in place and there is no more risk of accidents."
Crews will be allowed to clear the crane and the metal roofing structure after getting clearance from civil defence authorities, which is expected soon.
Associated Press writer Jenny Barchfield in Rio de Janeiro contributed to this report.