The World Health Organisation (WHO) researchers on Thursday, after the end of their quarantine in China, began investigations hoping to learn more about the origins of COVID-19.
China had required that the team spend a 14-day quarantine period in a hotel before they could begin their investigations in the city of Wuhan, where the virus is believed to have crossed from animals to humans in 2019.
China has disputed the theory that the disease started in Wuhan, even though that is the site of the first known instances of the disease, possibly because it does not want to be blamed as the source of the pandemic.
It has lashed out against countries like Australia for demanding an investigation.
The WHO mission there was delayed at least once due to visa paperwork problems.
But Chinese state TV reported on Thursday that the team would get started.
The 13 experts want to conduct interviews and visit hospitals.
They also plan to go to the food market where the coronavirus that causes COVID-19 was first encountered.
The team has spent the two weeks of quarantine conducting video conferences with Chinese colleagues.
But the researchers are playing down expectations, saying their main goal is to see which paths of inquiry are still open.