A World Health Organization team has emerged from quarantine in the Chinese city of Wuhan to start field work in a fact-finding mission on the origins of the virus that caused the COVID-19 pandemic.

The researchers who were required to complete 14 days in quarantine after arriving in China, could be seen leaving their hotel and boarding a bus on Thursday afternoon. It wasn’t immediately clear where they were headed.

The mission has become politically charged, as China seeks to avoid blame for alleged missteps in its early response to the outbreak. A major question is where the Chinese side will allow the researchers to go and whom they will be able to talk to.