India has issued notices to messaging platforms Telegram and Signal asking them to explain safeguards around features that allow users to post messages without revealing their phone numbers, a government source said.
The notices mark a further escalation of India's policing of online platforms, from blocking an entire app, when it temporarily blocked Telegram last month, to vetting individual product features across multiple services.
Telegram and Signal were asked on Thursday to detail how they protect users from impersonation and misuse enabled by features that let people interact without revealing phone numbers, the source said, speaking on condition of anonymity.
India's IT ministry, Telegram and Signal did not immediately respond to requests for comment.
On Wednesday, India's IT ministry directed WhatsApp to freeze the rollout of its own planned username feature and justify it within three days or face regulatory action, according to a government letter.
India says that anonymity granted by usernames could increase online fraud, phishing, digital arrest scams and impersonation attacks.
Prime Minister Narendra Modi's government has clashed repeatedly with global tech platforms. It locked horns with Elon Musk's X over content-takedown orders and tightened rules in February requiring platforms to remove government-flagged content within three hours, down from 36 previously.
The Internet Freedom Foundation, a digital rights group, called on the IT ministry to withdraw all three notices, saying the notice to Signal, an encrypted messenger used by journalists and activists, struck directly at protected speech.
"This is a dragnet, it is widening, and it has no basis in law".

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