A Bhopal court on Tuesday sent accused mastermind Balram, Manish, Mohit and Dhruv in the Bhopal espionage case to police remand till February 18.
However, accused Manoj and Sandeep have been sent to jail.
In a major breakthrough, the Madhya Pradesh Anti-Terrorist Squad (ATS) earlier on February 9 busted an international call racket that allegedly helped ISI agents to spy on India's military operations.
"Two men were arrested in Jammu in November '16 for collecting and using information of strategic interests for espionage. They were being funded by a person in Satna. Five persons from Gwalior, three from Bhopal, two from Jabalpur and one from Satna arrested," MP ATS chief Sanjeev Shami told the media.
Shami said the accused converted internet calls to cellular network and acted as medium for overseas handlers to contact people in India.
"The arrested men are accused of supplying information regarding army and Air Force in Madhya Pradesh. Complicity of some employees of telecom companies also surfaced," he said.
In January, the Uttar Pradesh ATS had arrested 11 people who were running a similar exchange.