The novel coronavirus has hiked demand for Amazon’s (AMZN) delivery service as hundreds of millions of Americans are forced into their homes. But the global pandemic has also prompted fear and frustration among many of the company’s warehouse workers, who have staged walkouts nationwide accusing the company of inadequate safety measures and insufficient paid leave as more than 50 facilities report infections.

On Monday, the confrontation escalated at a facility in Staten Island as dozens of workers walked off the job for a second time, organizers said, just one week after holding an initial strike. Organizers said that 26 cases of the virus had been reported at the warehouse, a sharp increase since the first reported case at the facility on March 24.

(When given an opportunity, Amazon did not dispute or confirm the number of cases at the warehouse. However, in a statement on Monday night, Amazon Spokesperson Rachael Lighty challenged the claim by organizers that 50 workers had walked out on strike, saying “less than 10 people participated in today’s demonstration, half of whom were not Amazon employees.” )

Amazon has rebutted the worker criticism, citing plans to implement temperature checks and provide protective masks for employees at all of its facilities in the U.S. The company said temperature checks already went into effect at the Staten Island facility on March 29.

Other protective efforts made by the company in recent weeks include enhanced cleanings at some warehouses and paid sick leave made available for all employees diagnosed with coronavirus.

The additional protections do not allay the fears of protesting workers, who have criticized the company’s continued operation of warehouses and instead called for the temporary closure of all facilities in the U.S. for deep cleaning as well as full pay paid leave during that period.

“This is blood money,” says Jordan Flowers, 21, a warehouse worker at the Staten Island facility who helped organize the walkout, referring to the money Amazon makes while workers are at risk. “We shouldn’t have to come to work worried about catching the virus.”

Flowers, who says he is at heightened risk because he suffers from an autoimmune disease, worked his last shift on Feb. 28 and says he will not return until the warehouse closes and undergoes a cleaning. He does not get paid while he doesn’t work.

“I want to know I’m in a clean workspace,” he says. “This is serious — we’re basically a breeding ground.”

In a statement, Amazon praised its employees for working under duress but rebutted claims that it has not taken sufficient action to address the coronavirus outbreak.

“Our employees are heroes fighting for their communities and helping people get critical items they need in this crisis,” says Rachael Lighty, an Amazon spokesperson. “Like all businesses grappling with the ongoing coronavirus pandemic, we are working hard to keep employees safe while serving communities and the most vulnerable.”

“We have taken extreme measures to keep people safe, tripling down on deep cleaning, procuring safety supplies that are available and changing processes to ensure those in our buildings are keeping safe distances,” Lighty adds.

Fifty workers participated in the walkout on Monday, according to advocacy organization New York Communities for Change, or NYCC, which has helped organize workers at the Staten Island warehouse. The turnout on Monday marks a slight dip in numbers for the walkout, which included more than 60 workers last Monday, according to NYCC. (Amazon says that the walkout last Monday included only 15 workers.)

Organizers of the walkout on Monday cited text message updates sent by Amazon managers to employees as evidence to support the claim of 26 coronavirus cases among workers at the Staten Island facility.

Last Monday, workers at the same Staten Island warehouse similar walked out during a shift over infection fears, and the dispute deepened when later that day the company fired one of the participating workers, Chris Smalls, for allegedly violating social distancing guidelines. Smalls, union leaders, New York’s attorney general, and elected officials like Democratic New York Rep. Alexandria Ocasio-Cortez have publicly criticized the company’s conduct toward him.

Two days later, leaders of the some of the nation’s largest labor organizations including AFL-CIO, the Service Employees International Union, and the American Federation of Teachers — which count tens of millions of members combined — called on the company for the reinstatement of Smalls and the temporary closure of all U.S. warehouses as well as full compensation for workers until it addresses their health concerns.

The letter questions the veracity of Amazon’s public statements about steps it has taken to address safety concerns at its facilities, which include enhanced cleanings the company has conducted at some warehouses and paid sick leave it has made available for all employees diagnosed with coronavirus, among other steps taken to address the health risks.

The letter is also signed by dozens of elected officials in New York, where Attorney General Letitia James is considering legal options to punish Amazon for the seemingly retaliatory firing of Smalls, Yahoo Finance’s Alexis Keenan reported. (James did not sign the letter).

The company has more than 110 fulfillment centers in North America, according to its website. The warehouse in Staten Island is one of the company’s largest urban facilities, the Verge reported last year. The facility is 855,000 square feet and has 4,500 workers.

The Retail, Wholesale, and Department Store Union, or RWDSU, which has helped organize workers at the Staten Island warehouse, released a statement in support of the walkout.

“Clearly Amazon must do better for its workforce,” says Stuart Appelbaum, the president of RWDSU. “Amazon needs to listen to its workers who are at risk during this global pandemic.”

Flowers, the warehouse worker at the Staten Island facility, said the company should treat its workers with the same respect it treats the customers.

“The customer is always right,” he says. “Right now the employee is always right: We’re asking for you to help us.”

The story has been updated to included a statement provided to Yahoo Finance by Amazon on Monday night.

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