While DRDO sources termed the transfer as "routine", the officer has alleged that he was singled out by two senior officials within the organisation, including former chief Avinash Chander, who demitted his office on January 31.
The incident came just days after the successful canister launch of the inter-continental missile on January 31.
Gupta has complained to the mnistry that he received the letter, dated January 9, only on February 2 when he reached his office after the successful launch.
"With all humility and respect, I wish to bring to your notice that on February 2, I was relinquished from the post of project director Agni-V.
Incidentally Gupta's name had come up in connection with the sudden termination of Chander's contract by the government, 15 months ahead of his tenure.
It was then rumoured that one of the reasons for Chander's removal was three complaints filed by individuals including by Gupta who has denied any such move.
DRDO sources insisted that such transfers are routine when a project enters into a different phase.
"The Agni 5 is no longer in development phase. It is in production and induction phase and hence transfers are routine since the services of an officer can be used somewhere else. A new person to take care of production is also brought in," a source said.
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