The World Health Organization’s chief said a mission to study the origins of the coronavirus in China didn’t adequately analyze the possibility of a lab leak before it concluded that the pathogen probably spread from bats to humans via another animal.

Director-General Tedros Adhanom Ghebreyesus said even though the international team of scientists determined that a leak is the least likely hypothesis for the origin of the pandemic, it requires further investigation. He said he’s ready to deploy additional missions involving specialist experts as he doesn’t believe the assessment was extensive enough.

He made the comments in a briefing to WHO member countries yesterday. Although Tedros has consistently said all options remain on the table and the WHO wouldn’t shut down any lines of inquiry, Tuesday’s comments mark the first time he’s openly speculated about the possibility of a leak. The WHO chief was criticized by Trump administration officials for being too deferential to China in the early days of the pandemic.

Sisanda Mpiti.