A team from the World Health Organization visited on Sunday a market in the central Chinese city of Wuhan, where many people were confirmed to have contracted the novel coronavirus in the initial stage of the outbreak in late 2019.
But it is uncertain whether the probe will help identify the origins of the virus, as more than a year has passed since the first infection case was spotted in Wuhan, a business and transportation hub with a population of some 11 million.
One of the experts told Kyodo News that the WHO group would inquire into how animals were traded at the market and interview those who are familiar with the mechanics of the place.
The WHO team consists of 10 experts, including Ken Maeda, a veterinary microbiologist at Japan's National Institute of Infectious Diseases. After quarantining for two weeks, they started a full-fledged investigation on Thursday.
The Wuhan market, where wild animals such as bats and snakes were sold alongside seafood, has been closed since January 2020.
During their stay in Wuhan possibly through early February, the experts are also planning to examine a research laboratory in the city, amid claims by some that the virus which causes the COVID-19 disease was accidentally released from there.
Last year, then U.S. President Donald Trump said he was confident the virus had originated from the infectious diseases lab and threatened to punish China for what he perceived as its lackluster response that allowed the virus to spread worldwide.
The WHO team had initially planned to visit China earlier this month, but its arrival was delayed after it took the experts longer to gain permission to enter the country.
WHO Director General Tedros Ghebreyesus said earlier he was "very disappointed" with China about the team's delay in getting into China.
Although the WHO sent a small group of experts to China for a preliminary probe in July, they did not visit the market or the laboratory in Wuhan.
Since first being detected in Wuhan, the virus erupted into a pandemic that has infected over 100 million people and caused more than 2.2 million deaths across the globe, according to data compiled by Johns Hopkins University.