Amazon staff overheard a suspected sexual assault on Alexa but were told it was 'not their place' to intervene, according to reports.
Bloomberg revealed the little-known existence of the human monitors who eavesdrop for the popular home assistant device to improve its voice command services.
But the global tech giant insists it respects users' privacy and security after questions were raised about the 'listeners'.
Not all Alexa users will be aware that what the helpful cylinder sitting on their sidetable in their private home overhears might also be listened to by strangers sitting behind computers thousands of miles away.
But employees who do just that claimed to Bloomberg they had overheard disturbing episodes during the course of that work.
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The news site claims two sources working for Amazon reported to their management they thought what they heard may have been sexual assaults over Alexa.
The two Romanian-based employees were allegedly told it wasn't Amazon's job to interfere when they flagged their concerns, Bloomberg reports.
In response to the allegations, Amazon told the news outlet it took customers' security and privacy seriously.
“We only annotate an extremely small sample of Alexa voice recordings in order [to] improve the customer experience," a spokesman told Bloomberg.
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"For example, this information helps us train our speech recognition and natural language understanding systems, so Alexa can better understand your requests, and ensure the service works well for everyone.
“We have strict technical and operational safeguards, and have a zero tolerance policy for the abuse of our system.
"Employees do not have direct access to information that can identify the person or account as part of this workflow.
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"All information is treated with high confidentiality and we use multi-factor authentication to restrict access, service encryption and audits of our control environment to protect it.”
Bloomberg's report illustrated how while many believe voice-activated Alexa to be fully-automated, a global team of human monitors are actually listening in to review some audio clips.
The teams reportedly exist for quality control, to ensure the digital assistant's voice command response is reviewed and improved for its tens of millions of users.
The listeners told Bloomberg they pick up private audio users would probably like to think no one can else hear - such as their shower singing.
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The employees' job is said to be to transcribe and annotate voice clips when Alexa has been accidentally triggered, and also understand quirks of human speech so the devices can respond better to commands.
Bloomberg also reported that workers shared amusing clips among themselves during their workday.
Amazon's popular digital home assistant is feted for its technology's pioneering use of voice-activated artificial intelltigence.
Workers in Bucharest claimed to Bloomberg some reviewers listen to as many as 1,000 audio clips per nine-hour daily shift.
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Employees help Alexa learn idiosyncrasies of common speech- such as how a person might ask for the nearest "Greek place" - but probably mean a restaurant rather than a church, according to the report.
The global tech giant's marketing claims have focused heavily on how the wonder device learns from "the Cloud."
But fears about exactly who can eavesdrop and collect audio recording private happenings in users' homes and offices has caused some to view Amazon's prize product with suspicion since its release.
The Mirror has approached Amazon for comment.
