The emails were sent from the ID black.monolith@gmail.com, hurled various allegations against Patil and also threatened her with dire consequences, official sources said.
Patil had also received a threatening email on Sunday which was traced by the security agencies to Tamil Nadu.
However, Airtel, the service provider of the Internet connection, was unable to give details about the connection.
All the emails were received on the President's official website--www.presidentofindia.gov.in--and the sender seemed to be a maniac, officials attached with the probe said.
The Tamil Nadu police had been alerted and a team of experts from central security agencies were working to find the creator of the emails. Security agencies are also in touch with officials of the portal gmail.com to trace the senders of the threat mails, the sources said.
The police have also identified the owner of the car with fake national emblem, which was intercepted during President Pratibha Patil's visit to Pune.
The seized car had been registered under the name of one Pintoo Sengupta, hailing from Delhi, a police official said.
A hunt has been launched to nab the suspect,who fled from the car when it was being escorted to police commissionarate in Pune, he added.
