COAI advised users not to divulge personal details like voter ID number, bank account and credit card information to false calls which say that they have won a prize, adding that such calls has been traced to have cross the border origin.
"I have been given to understand that in these types of phone frauds, the fraudsters pretend to be representative of a mobile operator. The callers trick users into giving personal information and asked them to pay money saying that they have won a prize," COAI officiating Director General T R Dua said.
Dua also advised against using mobile browers while surfing through the sites as some sites contain unreliable and questionable content.
The COAI declaration came after reports of the growing number of such calls lately.