Reliance Jio Group Chief Technology Officer Jagbir Singh had joined the company before the soft launch of 4G services.
Prior to this assignment, Singh was working with Samsung, and had previously worked with Airtel for about a decade.
According to a source, he is moving back to Delhi but did not disclose any further details.
Email sent to Reliance Jio did not elicit any reply.
Bharti Airtel's Chief Technology Officer for mobile networks, Shyam Prabhakar Mardikar has also put in his papers.
When contacted, Bharti Airtel spokesperson confirmed the development.
According to the source, Mardikar has resigned to move up the ladder in his career path.
Mardikar has been with Airtel since August 2012. This was his second stint with the telecom major. Earlier, he has served Airtel for about a decade from 2001-2010 after quitting his job at the Department of Telecom.
He was serving as CTO of Airtel's mobile network since January 2017.
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