The much-anticipated and delayed World Health Organization team investigating the origins of the coronavirus has finally arrived in Wuhan, only to hit another setback.
Two members have been forced to remain behind after they tested positive for coronavirus antibodies.
The rest are quarantining for 14 days.
It's been a year since the first reports of the disease emerged in Wuhan.
The international team of scientists was supposed to arrive a month ago but was delayed by the Chinese government, which drew a rare public criticism of Beijing from the WHO at the time.
Beijing says the delay was a "misunderstanding."
The United States has also criticized the terms of the visit, under which Chinese experts have done the first phase of research. Washington has long-accused Beijing of lack of transparency, and hiding the extent of the initial outbreak.
Meanwhile, the Chinese government is pushing a narrative that the virus may have existed outside China before it was discovered in Wuhan, partly due to scientific papers that suggest it may have circulated in Europe in 2019.
One WHO team member however, has warned that while they don't expect any hindrances as they scour the city, the scientists may not find clear answers here.