At least nine people fell through a section of the highest bleachers at the Fonte Nova stadium in the coastal city of Salvador, and eight were killed, said Maj. Edmilson Tavares of the city's federal police.
Television images showed what appeared to be a hole in the bleachers. Tavares said it was not clear what caused the collapse, but Brazilian media reports said the 56-year-old stadium recently came under heavy criticism for the precarious condition of its stands.
The accident happened as the game ended, when fans of the Bahia soccer team went into a wild celebration, storming the field when their team managed a goalless draw with Vila Nova, securing Bahia a place in the nation's second division.
Fans were jumping up and down in glee when a hole measuring several meters (yards) wide opened in the concrete floor of the stand. The victims fell several stories to the ground.
Tavares said he could not immediately confirm how many people had been injured, but Globo TV reported dozens were hurt.
About 60,000 people were at the stadium for the game, and many didn't realize that the section of bleachers had given way as they invaded the field in celebration.
The stadium was built in 1951, according to the Web site of Salvador 's A Tarde newspaper.
A survey of soccer stadiums released last month by Brazil 's Sinaeco association of architects and engineers said the Fonte Nova's stands were "in ruins," A Tarde reported.
The newspaper said Fonte Nova was evaluated as part of a study of Brazilian soccer venues because Brazil will host the 2014 World Cup. Salvador would almost certainly get some of the games.
Brazil, which has won a record five World Cups, was awarded the right last month to host 2014 tournament by FIFA, soccer's governing body. Latin America's largest country hosted the competition once before, in 1950.
The state governor of Bahia state, Jacques Wagner, ordered the Fonte Nova stadium closed while authorities investigate the cause of the accident.
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