The Indian Air Force has taken a Group Captain into custody after he was accused of passing classified documents to a woman

The IAF's counter-intelligence wing has taken the officer, posted at the IAF headquarters, in custody for further questioning. The security unit is probing possible espionage charges against the officer, who is not from the flying branch.

The officer befriended a woman on Facebook and later continued their communication on WhatsApp. Because of his seniority and posting, he was privy to certain information, some of which have been passed on to the woman through WhatsApp. There is also suspicion of him being a case "honey trapping".

"The officer was indulging in certain unwanted activities through unauthorised electronic devices which is against existing orders. The unwanted activities were discovered during routine counter-intelligence surveillance," sources said.

The IAF has not officially commented on the incident.

"Regular counter-intelligence coverage in liaison with central agencies is being maintained for all the units and establishments (of the armed forces) to defeat subversion and espionage attempts of foreign intelligence agents. Further, service personnel are regularly educated on the modus operandi of foreign intelligence operatives including awareness drive on threats from social media," former defence minister Manohar Parrikar informed the Parliament in 2016.

In December 2015, one person each from Army and Air Force was arrested for espionage activities and the IAF person was dismissed from service.

The armed forces have strict rules on the use of social media. The personnel are barred from posting any photograph or information on their ranks, place of work, location, infrastructure and operations.

Also, the computers used in the three services and the defence ministry to handle sensitive information are not connected to the internet. There are also strict restrictions on the use of smartphones.