People working for Amazon have written to the company's CEO, Jeff Bezos, to protest the sale of facial recognition tools and other technology to police departments and government agencies.

The workers cite the use of Amazon technology by the US Department of Homeland Security and the Immigration and Customs Enforcement (ICE) agency, which have been criticised for enforcing Donald Trump's "zero tolerance" policy, which has seen parents separated from their children at the US border.

"As ethically concerned Amazonians, we demand a choice in what we build, and a say in how it is used," the letter states. "We learn from history, and we understand how IBM's systems were employed in the 1940s to help Hitler.

"IBM did not take responsibility then, and by the time their role was understood, it was too late.

"We will not let that happen again. The time to act is now."

Holocaust experts claim IBM's German subsidiary directly supplied the Nazis with technology which assisted the operation of concentration camps at Auschwitz and Treblinka.

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The letter comes days after 19 Amazon shareholders wrote to Mr Bezos urging him to halt the sale of facial recognition to police and government agencies, as they fear the firm's involvement could ultimately drive down its value.

The American Civil Liberties Union (ACLU) revealed earlier this year how Amazon is marketing its powerful AWS Rekognition tool to law enforcement agencies, a practice the workers claim is making the firm implicit in alleged human rights abuses.

“We are concerned the technology would be used to unfairly and disproportionately target and surveil people of colour, immigrants, and civil society organisations," the shareholder's letter stated.

Amazon refused to provide a comment on the record about the letter.

The company has previously defended the development of Rekognition and denied it is used for surveillance.

"As a technology, Amazon Rekognition has many useful applications in the real world," a company spokesperson said.

"Our quality of life would be much worse today if we outlawed new technology because some people could choose to abuse the technology.”

In their letter to Mr Bezos, the Amazon workers said they would "refuse to build the platform" which powers ICE, or any technology used to violate human rights.

Listing three demands, the workers called on the CEO to stop selling the technology to law enforcement, stop providing infrastructure to partners which enable ICE, and implement stronger transparency measures.