The World Health Organization team leader who first appeared to rule out the Wuhan lab leak hypothesis has now backed off, saying it remains under consideration and will be reviewed further.

Peter Ben Embarek said last week that the possibility that the coronavirus may have escaped from the Wuhan Institute of Virology didn’t merit further inquiry. Days later, however, WHO Director-General Tedros Adhanom Ghebreyesus reversed that by saying more study was needed, and Embarek seemed to echo that on Monday.