Dubai's Expo 2020 acknowledged for the first time on Sunday that three workers had died from the coronavirus over the course of building the world's fair during the pandemic, as the prestigious event draws scrutiny of labor conditions in the United Arab Emirates.

When asked at a press conference about deaths among Expo's vast foreign labor force, spokesperson Sconaid McGeachin said three workers had died from the virus in addition to three from construction incidents, without specifying when. She declined to describe the extent of the coronavirus outbreak among workers on site.

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McGeachin again claimed the information about worker casualties was previously available, without elaborating. However, authorities in the run-up to the $7 billion fair had not offered any overall statistics on worker fatalities, injuries or coronavirus infections despite repeated requests from The Associated Press and other journalists.

The statement comes a day after Expo offered conflicting reports about how many workers had died in industrial incidents on site, before settling on three.

The UAE long has faced criticism from human rights activists over poor treatment of the legions of low-paid migrant laborers from Africa, Asia and the Middle East who power the country's economy. Dubai has gambled billions on its elaborate World Expo, hoping to make it a huge tourist attraction and a symbol of the country’s allure.

But problems have emerged. The European Parliament last month urged nations not to take part in Expo, citing the UAE’s “inhumane practices against foreign workers” that it said worsened during the pandemic.

To pay tribute to the thousands of workers who toiled to build the fairgrounds from scratch, the site features a somber worker's monument — stone columns wrapped with an engraved roll call of laborers' names at Expo's Jubilee Park, nestled between a performance stage and a popular Dubai bar chain.

The massive global event has also renewed criticism from human rights groups of the UAE's suppression of dissent and restrictions on free expression.

At a press conference Saturday, French Foreign Minister Jean-Yves Le Drian answered a question about the European Parliament's concerns over labor abuses in the UAE, saying that France would not join in its call for an Expo boycott and instead raise any potential issues with Emirati authorities “behind closed doors.” However, the sensitive exchange was inexplicably missing from the official Expo transcript of the news conference, raising concerns about transparency at the site.

“I will look into that,” said McGeachin when asked about the omission. “I would like to say that this is an oversight.”

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Meanwhile, Uganda’s long-serving President Yoweri Museveni arrived to visit his nation’s pavilion at Expo. He called the site and the Emirati effort to build the small city “a challenge to the Africans” as they had “turned a desert into a center of affluence.”

“Yesterday when I arrived, they took me for COVID test,” he said. “In Africa, sometimes we say, ‘Big people should not be checked.’”