Amazon asked police in Spain to intervene in a mass strike on Friday by enforcing worker productivity inside a Madrid warehouse, according to local reports.

Thousands of Amazon workers across Europe went on strike on Black Friday in protest of the working conditions at warehouses.

Spanish police were "dumbfounded" by Amazon's request, which they categorically rejected, according to El Confidencial.

Amazon denied the allegation, calling the reports "ludicrous suggestions."

Amazon asked police in Spain to intervene in a mass strike at a warehouse on the outskirts of Madrid, according to local reports.

Amazon wanted a police presence at the warehouse to ensure that productivity remained high within the fulfilment center, while workers staged their protest outside, according to Spanish newspaper El Confidencial.

A source at Spanish union CCOO, which helped coordinate the strikes, told Business Insider that Amazon "wanted to send the police inside the warehouse to push people to work."

Amazon strongly denied the claims and called it "the worst kind of misinformation."

The dispute erupted as thousands of Amazon workers across Europe staged strikes on Black Friday in protest of warehouse working conditions. Some 1,600 staff walked out in Spain.

Read more: 'We are not robots': Thousands of Amazon workers across Europe are striking on Black Friday over warehouse working conditions

Spanish newspaper El Confidencial reported that Amazon met with police officials after the strike was announced. It wanted local officers "to force employees to go to their respective jobs and ensure their performance was identical to that of a normal working day."

Amazon's request "dumbfounded" police, according to El Confidencial. "The request was categorically rejected by the police, who maintained that controlling labour productivity doesn't fall within its powers," a police source said.

Law enforcement officials reportedly emphasized to Amazon that Spanish law protects workers' right to strike. They told the company that police would be present at the strike but would limit themselves to keeping the peace.

Police presence at an Amazon warehouse on the outskirts of Madrid, Spain, on Black Friday 2018. AP

Amazon denied that it had asked police to intervene in the strike. A spokeswoman told Business Insider:

"Amazon is a responsible business that puts its customers and associates first. We always work with public authorities, including the police, to ensure the safety of our people and our operations.

"However any suggestion that we have used this relationship in an improper way is categorically wrong. Anyone who understands the way businesses and local authorities work will know that these ludicrous suggestions are the worst kind of misinformation."

Madrid police were unavailable for comment.

This is not the first time Amazon has asked police to intervene in Amazon warehouse protests in Spain, El Confidencial notes. When workers went on strike on Prime Day in July, Amazon asked police to guarantee workers access across the picket line and to trucks carrying merchandise. The strikes in July resulted in clashes with police, including some arrests.

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