New York City’s Commission on Human Rights will launch an investigation into Amazon for firing a worker who organized a protest this week over fears of a coronavirus outbreak at the Staten Island warehouse where he worked. New York City Mayor Bill de Blasio announced the investigation on Tuesday.

The former employee in question, Chris Smalls, recently organized a walkout of about 50 people at a fulfillment center in Staten Island to protest the company’s decision to keep the facility open despite allegations that several associates have been infected with Covid-19. Smalls and other employees demanded that Amazon shut down the facility for a minimum of two weeks and provide workers with better health protections from the coronavirus.

Amazon said it fired Smalls for showing up to work after being in contact with a colleague who was diagnosed with Covid-19 and being asked to stay at home. But Smalls alleged to Recode that Amazon fired him because of his activism.

“The allegation is, because he spoke up for the safety of his fellow workers, he was fired. I have ordered the city’s Commission on Human Rights to investigate Amazon immediately to determine if that’s true,” said de Blasio at a press conference on Tuesday. “If so, that would be a violation of our city human rights law. We would act on it immediately.”

Amazon did not immediately respond to a request for comment.

The mayor’s announcement comes as grocery, delivery, and shipping workers at companies like Amazon, Instacart, and Whole Foods (which is owned by Amazon), have been protesting their working conditions during the coronavirus pandemic. These workers say there is an urgent need for companies to better protect employees from getting sick by providing benefits like more paid time off, sanitation equipment, and hazard wages.

Their fears are especially acute in New York, which has become the US epicenter of the outbreak, and where the Staten Island facility — one of Amazon’s busiest fulfillment centers in the US — is located. On Monday night, New York State Attorney General Letitia James called Amazon’s firing of Smalls “disgraceful” and urged the National Labor Relations Board to investigate the company. While Amazon has denied any retaliation in its firing of Smalls, the new investigation is drawing further attention to the concerns of blue-collar workers who are keeping US supply chains running and providing essential goods and services during the pandemic.

Amazon told ABC News that it terminated Smalls after he ignored multiple warnings to stay at home under quarantine after being in contact with a colleague who had tested positive for Covid-19.

Smalls denied this, telling Recode that his manager told him to self-quarantine on Saturday and that he hasn’t been inside the Staten Island facility since — only outside the building in the parking lot to protest on Monday, where he says he tried to stay 6 feet away from other people.

“I didn’t violate any safety protocols, and I have nothing to hide,” Smalls told Recode. “If I should be quarantined, the whole entire department of at least 400 people should be quarantined. This was a direct target to silence me.”

He told Recode that he plans to take legal action against the company for what he believes is wrongful termination.

It will be up to New York City government officials to determine what really happened here, but the mayor’s announcement is a sign that the labor practices of companies like Amazon are going to face mounting scrutiny as their employees keep showing up to work during the pandemic.