A member of Uganda's Olympic team has tested positive for coronavirus upon arrival in Japan - the first detected infection among arriving athletes for the Tokyo Games.
A nine-strong party of Ugandan athletes - including boxers, coaches and officials - arrived at Tokyo's Narita airport on Saturday.
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They are the second team to arrive after Australia's women's softball squad landed on June 1.
The team member who tested positive was not identified and the eight other athletes left the airport early Sunday by chartered bus for Osaka.
A government official told reports the athlete tested positive during screening at the airport.
Local media reported the person tested twice but their condition remained unknown.
"I heard the person has been isolated based on regulations," Hidemasa Nakamura, the Tokyo 2020 Games delivery officer, told reporters.
The Asahi newspaper reported the nine Ugandan athletes were all fully vaccinated with the AstraZeneca jabs and had negative PCR tests before boarding.
Yasutoshi Nishimura, a minister in charge of economic policy, said the government was looking into what had happened with border controls.
Last week organisers released virus guidelines for athletes as part of their effort to hold the Games safely even though the pandemic has not yet been brought under control.
Positive test sparks fresh concerns about Tokyo Olympics
Critics have raised serious questions about the risks of holding the Olympics amid a pandemic.
But the International Olympic Committe, Tokyo organisers and Japanese government insist the Games can be held safely.
Uganda is seeing an alarming rise in Covid-19 variants and has just tightened lockdown measures. About 590 deaths have been reported there, likely an undercount given the scarcity of testing.
Japan requires a two-week quarantine for overseas arrivals, but Olympic teams aren't subject to the same border controls.
Olympics organisers are expected to decide on Monday on allowing some local fans in the stands for the Games.
Plans for mass public viewing sites in Tokyo were cancelled on Saturday, while fans from abroad were banned several months ago.
A state of emergency to curb the spread of the virus in Tokyo, Osaka and other urban areas ends on Sunday, although daily cases are still growing by several hundred.
There has been no lockdown in Japan.
The so-called emergencies, which have lasted for most of this year, focus on having restaurants and stores close early, limiting crowd size at venues, and asking people to social distance, work from home and wear masks.
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