Indian police say they have arrested a man suspected of passing military secrets to arch-rival Pakistan.
The man, an Indian citizen, was held in the western state of Rajasthan near the two countries' border.
Police say he passed details of military exercises held last week to Pakistan's Inter-Services Intelligence.
India and Pakistan frequently accuse each other of spying. The arrest comes after weeks of tension over the disputed territory of Kashmir.
The alleged spy is accused of "passing information related to Indian defence installations and military activities", senior police officer DS Dinkar told AFP news agency.
One report says his telephone calls to a relative in Pakistan, who it is alleged works for Pakistani intelligence, were intercepted.
The man was arrested by army intelligence at his house in a village near the town of Pokhran on Sunday and is being questioned by security agencies.
He appeared in court in Jaipur on Monday and was remanded in custody, police sources said.
Prime Minister Manmohan Singh and President Pranab Mukherjee both attended the war games, codenamed "Iron Fist", which were held near Pokhran on Friday.