The website of the Indian Embassy here has been attacked twice by Chinese hackers, prompting the mission to boost its cyber security.

Reliable sources in the Indian Embassy said at least two cyber attacks were traced to Chinese servers, but denied leakage of any confidential information, which is processed by "standalone" computers.

The embassy's Local Area Network (LAN) also has no direct internet access and the firewall has been fortified, they said, adding the only hacking victim was the official website, maintained by the information wing.

The website allows for online filling of visa and passport applications.

"The indianembassy.ru website in the public domain was affected to some extent that e-mail IDs of the senior officials were cloned in the .com or gmail domains to spread the malware," the sources said.

"For example for the legitimate 'infowing@indianembassy.ru', IDs like 'infowing@indianembassy.com' and 'infowing@gmail.com' were used to spread spam with malware," the sources said.

In a recent incident, the 'Daily Media Digest' issued by the Information Wing in the evening was received by its recipients, including Moscow-based Indian journalists, early morning and instead of word document, it had RAR archive arrangement.

The prompt warning circulated by the embassy not to open the attachment saved many computers from the fresh lot of malware.

The incident assumes significance in the wake of a report about alleged Chinese cyber espionage which has infected scores of Indian government and defence related sites.

US and Canada based Information Warfare Monitor and Shadowservers Foundation in their report 'Shadows in the Cloud' had traced China's Chengdu based servers of ex-filtering sensitive information from the Indian computers, including Indian diplomatic missions in Moscow, London and Washington.

Commenting on the report, Russian media had raised concerns about sensitive and secret information about Moscow and New Delhi's defence cooperation falling into the Chinese hands.

Kommersant daily had said even in the cyber age the Russian missions use well tried method of using old typewriters and a sheet of paper to guard their secret information.