It looks like a hair coming out of the eye… but the more they pull, the longer it gets.
Many thought it was some kind of parasite or something trapped inside the eye. But no. What appears in the images is a surgical suture used after corneal surgery. That is why the thread seems endless as they slowly remove it.
The detail that shocked people the most was the calm with which they perform the procedure, while the strange filament keeps coming out in front of the camera.