Delhi police said Tuesday they have arrested a former Indian Air Force officer on charges of passing secrets to Pakistan's spy service.
Police said the man, who is accused of giving details of air force exercises to Pakistan's powerful Inter-Services Intelligence (ISI), had fallen victim to a "honey trap".
"Ranjith KK has accepted to have passed Air Force-related information pertaining to a recent Air Force exercise, movements of aircraft and deployment of various units in Air Force," said Ravindra Yadav, Delhi police joint commissioner of crime, in a statement.
The arrest comes days after Indian Prime Minister Narendra Modi paid a surprise visit to his Pakistani counterpart Nawaz Sharif to try to ease troubled relations.
The nuclear-armed rivals frequently accuse each other of spying on military activities.
The two have fought three wars since gaining independence from Britain in 1947 and a lasting peace deal has so far proved elusive, with deadly violence still flaring in the disputed territory of Kashmir.
Police said the ISI used a woman to lure him into passing on top-secret information through mobile phone and the Internet.
"As per the investigation so far, it has been assessed that (he) was befooled by the cross-border spies," Yadav added.