Two people working at Sao Paulo's Arena Corinthians that will host the opening ceremony of the 2014 World Cup died at the construction site after a crane collapsed on Wednesday afternoon.

The victims were identified as Fabio Luiz Pereira, 42, a Munck operator from BHM company, and Ronaldo Oliveira dos Santos, 44, an assembler from Conecta, according to a statement released by Odebrecht Infrastructure, a construction company building the stadium.

The crane lifting the last module of the stadium's metallic roofing structure toppled, which led the module to fall onto a circulation area of the east building and partially damaged the LED facade,  the statement added.

Odebrecht Infraestrutura and Sport Club Corinthians Paulista expressed regret on the accident and said "all efforts are being concentrated on offering complete assistance to the families of the victims."

The Wednesday's accident has further cast doubts if the stadium will be ready to host the world's biggest sporting extravaganza on time, as the construction work is expected to be delayed.

According to Reuters, Odebrecht Infrastructure said that construction work would resume by Monday, but the union representing the workers said construction could be frozen for up to 30 days while authorities investigate. It also said that workers had been trying to complete the Sao Paulo stadium before the December deadline imposed by FIFA.

With fatal accidents being reported at three World Cup stadiums - Sao Paulo, Brasilia and Manaus - FIFA has expressed concerns on the safety of workers. "The safety of workers is the top priority for FIFA, the LOC and the federal government" it said in a statement. "Wish to send our heartfelt condolences to the family of the workers who tragically died today," FIFA added.

The construction work at the Arena de Baixada in Curitiba was stopped last month after a judge ordered suspension of all work at the site, citing safety concerns. Protesters also have hit the streets, pouring their outrage over extravagant spending on the facilities for the sporting event, when several basic amenities were overlooked.

Arena Corinthians, which is locally known as Itaquerao, is due to host the opening ceremony of 2014 World Cup. The world's biggest sporting event will be held from 12 June to 13 July 2014. 

(With Inputs from Reuters)

Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo
Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo
Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo
Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo
Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo
Arena Sao Paulo stadium
Workers stand near a crane that collapsed on the site of the Arena Sao Paulo stadium, known as "Itaquerao", which will host the opening soccer match of the 2014 World Cup, in Sao Paulo