In a video published to YouTube, an unidentified protester holding a video camera, filming a police line during the early hours of Thursday, Nov. 3, is apparently shot with a rubber bullet even after repeatedly asking officers, “Is this okay?”

Rubber bullets, though considered non-lethal, have killed people before. They can also cause serious internal injuries and even break bones. Despite their name, rubber bullets are small metal cylinders merely coated with a layer of rubber, and can be launched from traditional firearms. (Update: There’s been some speculation that this person may have been shot by a beanbag round instead, but it remains unclear.)

The incident took place following Thursday’s call to general strike, which saw tens of thousands of protesters shut down one of the city’s major highway overpasses. Though the event was largely peaceful, police said they made 103 arrests, mostly for protesters who failed to disperse after being told to leave public spaces. There were also reports of some vandalism and broken windows, although it was not widespread.