RIO DE JANEIRO (AP) — Workers at Rio de Janeiro’s two airports have declared a 24-hour strike to begin at midnight Wednesday, on the eve of the opening match of the World Cup.

Rio’s Galeao international airport is expected to be one of the country’s busiest during the monthlong soccer tournament. The walkout also will affect Santos Dumon airport, which provides domestic service, including flights to Sao Paulo, where the first World Cup game will be held Thursday.

Unions representing workers at the two airports including check-in counter clerks and baggage handlers are seeking raises of at least 5.6 percent.

A labor court has issued an injunction ordering the unions to maintain staffing at 80 percent of normal levels or face fines of up to $22,400.

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