More than two thirds of the venue’s 1,300 employees were absent from work Wednesday, Xinhua quoted a local daily O Globo.
World football’s governing body FIFA last week warned that local organisers faced a “race against a very tight timeline” to complete the stadium’s redevelopment in time for the World Cup, starting June 12.
Parana-state World Cup secretary Mario Celso Cunha admitted to be being concerned by the strike.
“We don’t know how long the strike will last, but if the strike doesn’t end soon, it’s going to be tough to meet the construction deadline,” Cunha said.
Transport workers have demanded pay increases of up to 22 percent, having rejected an offer of a 5.2 percent rise in line with inflation.
Arena da Baixada will stage World Cup group matches between Iran vs Nigeria (June 16), Honduras vs Ecuador (June 20), Australia vs Spain (June 23) and Algeria vs Russia (June 26).