New Delhi : After registering a Preliminary Enquiry against Google for alleged mapping of classified areas, CBI has sought help of Survey of India which has alleged that the Internet giant continued to "pollute" the web with classified material despite being warned against it.

As the probe continues, Surveyor General of India Swarna Subba Rao alleged that the Internet giant did not refrain from mentioning classified site even after having been asked not to do so.

"During their (Google's) Mapathon 2013 exercise, they collected lot of classified data and we had approached them to refrain from doing so when we came to know about it," Dr Rao told PTI from Dehradun.

He said, instead of desisting, Google "polluted the Internet" with the coordinates of classified locations on the map. "They (Google) have expressed their desire to meet me at some hotel but I have been firm of a meeting in office," he said.

The Survey of India (SoI), the official mapping agency of the country, is the complainant in the case. After initial probe by Delhi Police, the case was handed over to the CBI as the investigation involved a company which is based in the US.

Google had not taken permission from SoI before organising a mapping competition in February-March 2013 in which they asked citizens to map their neighbourhoods, especially details related to hospitals and restaurants.

Alarmed by Mapathon, SoI, India's national survey and mapping organisation under the Department of Science and Technology, asked the Internet giant to share its details and found that there were several coordinates with information on sensitive defence installations which are out of the public domain.

The CBI has examined Google-India's Legal Advisor Geetanjali Duggal and others so far. Asked for its response, Google India said "we continue to be in touch with relevant authorities and take national regulations and security very seriously.

"We are cooperating with the CBI's investigations and have submitted a detailed response to the queries that they have sent. We have nothing more to share at this point in time."

(PTI)