The Delhi Police on Wednesday received a phone call threatening to blow up the prime minister's residence, Rajiv Chowk metro station and Bangla Sahib Gurdwara, which later turned out to be a hoax.
The Delhi Police control room received the call at 8.30 am, a senior police official said.
"Operations were carried out in the above locations and it was found that the call was a hoax. The mobile number of the caller was traced to a location in Rohini in north-west Delhi," the officer said, adding the phone was switched off immediately after the call.
"We are trying to ascertain the identity of the caller," he said.
The city police had received a similar call of planting bombs at Red Fort last week. Mehfuz, who had made the phone call for "fun", was arrested.