YouTube employee describes seeing 'blood drips on the floor' amid active shooter reports

Some YouTube employees describe feeling an "earthquake" as a stampede of coworkers reportedly rushed by amid reports of an active shooter on their campus in California Tuesday. The San Bruno Police Department told Fox News they received at least 50 calls reporting gunshots and officers are responding.

Todd Sherman, who identifies himself as a product manager at the company, said he was in a meeting when he heard people running in the hallways. He exited the room with coworkers and followed the crowd.

"Seemed serious and not like a drill," Sherman said in a Twitter thread Tuesday afternoon. "We headed towards the exit and then saw more people and someone said that there was a person with a gun."

"I looked down and saw blood drips on the floor and stairs," Sherman continued. "Peaked around for threats and then we headed downstairs and out the front."

Lil Chen, a UX designer for YouTube Live, said online that she also saw "blood drops on the stairs" as she evacuated the building with her hands up.

"I’m shaking. This is surreal. I hope my colleagues are okay," Chen posted, adding that she was hiding behind another building with colleagues while police searched for the shooter. "There are helicopters. There are lots of police nearby."

Vadim Lavrusik, who also says he works in the product department at YouTube, said he heard shots and saw people running while he was sitting at his desk. 

"Now barricaded inside a room with coworkers," Lavrusik said in a tweet that has been shared tens of thousands of times.

About 20 minutes later, Lavrusik confirmed that he was safely evacuated, adding that he's "all shakin up."

Sherman also confirmed he exited the building safely, saying he was met outside with police cruisers and officers "with rifles ready."

Danny Keane, who says he's a designer at Google on Twitter, said the shooting was still active around 2 p.m. local time, though he noted that he's safe.

"Very tense times at @YouTube right now. Shooter is still active," Keane wrote. "I'm safe, but really sad to hear about fellow colleagues that were injured."

Hospital officials told KTVU that they received multiple patients. Here's what others in the area are sharing online: