Over 20,300 cases of cloning SIM cards have been reported till now, with Delhi registering the maximum violations, minister of state for communications and IT Milind Deora said in a written reply in the Lok Sabha on Wednesday.
He, however, said that no incidence has been reported so far of SIM card cloning with the help of a single missed call.
Cloning a SIM is the transfer of identity from one mobile phone to another. According to experts, most of the time, cloning a SIM requires physical access to it.
Last month state-run Bharat Sanchar Nigam Ltd. (BSNL) issued alerts to all broadband subscribers advising customers not to call back on some specified numbers as they might be susceptible to SIM card cloning.
According to the minister, Delhi has reported 18,547 cases, followed by Punjab with 1,738 cases.