Thousands of smartphone users in India were left puzzled on Friday when they found Unique Identification Authority of India (UIDAI) toll-free helpline number saved in their phonebooks by default.

Many people on Friday found their phonebook updated with UIDAI helpline number — 1800-300-1947.

There had been no earlier message seeking permission regarding the same, but the number automatically appeared in the contact list.

Several Twitter users took to micro-blogging site and questioned the step taken by the UIDAI once again flagging the security concerns.

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“This is no joke as it is on my phone too. I didn’t save this number. Check your phone asap, feeling worried,” a user tweeted with a screenshot.

A French security expert, Elliot Alderson, asked UIDAI on Twitter: “Many people, with different providers, with and without an #Aadhaar card, with and without the mAadhaar app installed, noticed that your phone number is predefined in their contact list by default without their knowledge. Can you explain why?”

Another Twitter user added, “The AADHAR helpline number mysteriously creeps up in my contacts today! As far as I can remember I didn’t save nor give anyone any sort of consent regarding this. Then how did this come up?! This is indeed shocking and well scary… Aren’t we liable for privacy?”

The UIDAI officials are yet to respond regarding the matter.