A member of the World Health Organisation team investigating the origins of COVID-19 has defended the credibility of its work amid mounting criticism.
Prof John Watson told the BBC that the trip to Wuhan, China - where the virus was first detected - was only a start and more research would be needed.
The US, UK and members of the team have complained of insufficient access given to the mission by the authorities.
China has insisted it was transparent.
The international team of experts concluded their trip to the city of Wuhan earlier this week without any definitive answers on what caused the outbreak.
Wuhan was the first place in the world where the virus was detected, in late 2019.
Since then, more than 108 million cases and 2.3 million deaths have been reported worldwide.
The WHO mission began in January, following months of negotiations with Beijing, and was closely-monitored by the Chinese authorities.
[Source: BBC]
