Swathes of empty seats visible during Thursday's World Cup match between South Korea and the Czech Republic have raised questions over FIFA's approach to record ticket prices for the tournament.

Many of the empty seats appeared to be located in VIP sections near the pitch, according to The Athletic, which said there appeared to be thousands of unoccupied places throughout the stadium.

Soccer's governing body, FIFA, reported a crowd of 44,985 at Mexico's Guadalajara Stadium, which has a capacity of 46,000. It did not confirm whether the figure was based on ticket sales or the number of fans who entered the ground.

Ticket prices for the tournament have increased fivefold compared to the 2022 World Cup in Qatar, according to the fan group Football Supporters Europe (FSE), which described the costs as "extortionate." FSE noted that World Cup organizers had promised tickets priced as low as $21 in a 2018 bid document.

The attorneys general of both New York and New Jersey have launched investigations into "impossibly high prices." The tournament is being held across the U.S., Mexico and Canada.

FIFA President Gianni Infantino defended the pricing strategy as recently as Wednesday, saying the costs were comparable to those of other major sporting events. He added, "If we do something wrong, then probably everyone selling tickets in North America is doing something wrong."

On the eve of the tournament, 29 games were sold out, and 75 had tickets remaining, according to the Associated Press.

Almost 180,000 tickets were still available on FIFA's official resale platform on Tuesday, the Financial Times said, with the median ticket price on there falling by 20 percent over the past month. Third-party resale sites such as StubHub and SeatGeek also have World Cup tickets for sale.

Following criticism, FIFA offered a smaller number of $60 tickets to all 104 matches to national federations for their regular supporters. Infantino said 130,000 tickets were offered in that category.

More tickets will become available closer to matches, Infantino said. "We also need always to keep some tickets for those teams who qualify for the additional rounds," he added.

A capacity crowd of 80,824 attended the opening match between co-hosts Mexico and South Africa in Mexico City earlier on Thursday, the AP said.