A worker has died at the Arena Pantanal in Cuiaba, one of the stadiums due to host World Cup matches next month.
At around 10.00am local time on Thursday, a construction worker was killed after suffering an electric shock at the stadium.
A statement from Secopa MT, the organisation body for the tournament in Cuiaba, confirmed the tragic news.
"The Special Secretariat of the World Cup Mato Grosso regrets to inform the death of Muhammad'Ali Maciel Alfonso, 32," it read.
"He was the victim of an accident caused by an electrical discharge on Thursday morning, while working on the 20th level in the eastern sector of the stadium.
"Ambulance teams and the fire department of the State of Mato Grosso assisted on site, where they went through all resuscitation procedures.
"Secopa MT send its sympathies to the family of Alfonso and will await the work of experts of the technical police, who will investigate the causes of the accident.
"The MT Secopa regrets the sad episode, which occurred on the eve of the inauguration of the Pantanal Arena and after the entire period of construction there has been no occurrences of other accidents on site."
The arena is due to host four World Cup matches at the finals, including Chile versus Australia on June 13, the second day of the tournament.
The worker is the latest to die during the building of Brazil's World Cup stadia.
In November last year, two people were killed when a crane struck the roof of the Arena de Sao Paulo, causing a partial collapse.
Further accidents have taken the lives of workers at the stadium in Manaus, while a third man lost his life in Sao Paolo following a reported fall in March.