Writer Chaédria LaBouvier reported that she had seen 14 San Francisco police officers subduing a homeless black man who had one leg outside Twitter headquarters.

In a column for Medium, LaBouvier explained that she recorded the incident on Aug. 4 during a visit to Twitter HQ.

Witnesses told LaBouvier that police had been called because the man was waving “sticks,” which later turned out to be his crutches.

Video of the incident begins with the homeless man hidden under a pile of police officers. As the man struggles, it becomes clear that he is wearing a prosthetic leg.

“It is often twisted and backwards in the video,” LaBouvier noted. “An officer can be seen at the 5 second time-mark stomping on the man’s prosthetic leg. In further efforts to subdue a man already on the ground with four people on top of him, they stood on his leg, held it, and twisted it around even after they had cuffed him and pinned him to the piss-stained concrete.”

“These incidents are so quotidian, so mundane, that they do not merit a mention in even passing on the local news. Which is to say, this is everyday harassment,” she lamented. “Yes, it’s racial profiling. Yes, it’s racism. Yes, it’s inequality. This is an American heritage.”

LaBouvier pointed out that none of the employees at Twitter or other tech companies came out to object as the 14 officers took down the one-legged homeless man. She argued that residents needed to get involved, ask questions and speak out.

“This happened in the heart of one of America’s most affluent cities, literally outside the headquarters of Twitter. One block away are the headquarters of Uber, which is on pace to be the fastest-growing company in history,” she wrote. “And not to my knowledge, did any of their employees or representatives come out to look at what the police were doing.”

“Perhaps they were looking from their lofts and skyscrapers, on their way to the coffee machines or the in-house catered lunch and did see, but they too have normalized this mundane, quotidian and brutal American heritage. Whatever the internal struggles were, no one came.”

The U.S. Justice Department recently filed court documents in an Idaho case which declared it unconstitutional to criminalize homelessness. Activists have said that San Francisco’s homeless policy runs afoul of the Justice Department guidelines. Under the city’s policy, homeless people can be constantly woken up and told to move.

According to the Coalition on Homelessness, the city handed out 11,000 citations to homeless people who were sitting on sidewalks between 7 a.m. and 11 p.m. in 2014.

Watch the video below.