Two Navy ships located near the target tracked and witnessed the missile hitting it accurately, he said.
During today's launch, the missile was fired from a mobile rail launcher, sources in Balasore said.
Defence Minister AK Antony congratulated DRDO chief VK Saraswat and the scientists involved in the Agni-III project on the "remarkable success" of the missile test.
The defence spokesman said the launch was part of the pre-induction trial and "now the missile system will be fully inducted into the armed forces."
A number of radars and electro-optical tracking systems along the coast of Orissa monitored the path of the missile and evaluated all the parameters in real-time, Kar said.
Equipped with a state-of-the-art advanced computer, the navigation system used for guiding the missile to its target is the "first of its kind", he said.