Vadim Lavrusik’s Twitter profile page

Twitter CEO Jack Dorsey tweeted that the company was “on it” as misinformation spread about the shooting at YouTube headquarters.

In the hours after an active shooter opened fire on the YouTube campus in San Bruno, California, on Tuesday, tweets flew with new details about the situation. But Twitter was also forced to scramble to stop the spread of false information on its platform.

The Twitter account belonging to one of the first YouTube employees to tweet about the incident, Vadim Lavrusik, appeared to be hacked. After Lavrusik had tweeted that he was safe, a number of fake tweets appeared. One asked people to “please help me find my friend” with a picture of YouTuber Keemstar, who hosts a popular news show. That…