India on Monday successfully test fired its nuclear-capable strategic ballistic missile Agni-IV, capable of hitting a target at a distance of 4,000 km.The army's strategic forces command fired the missile as part of a user trial from the A.P.J. Abdul Kalam island off the Odisha coast, defence ministry sources said."The test was a success," a Defence Research and Development Organisation (DRDO) source said.The indigenously developed surface-to-surface Agni-IV missile is a two-stage weapon system weighing 17 tonnes and is 20 metres long.It is one of its kind and represents a quantum leap in terms of missile technology. The missile is lighter in weight and has two stages of solid propulsion and a payload with re-entry heat shield.It is equipped with fifth generation onboard computer and distributed architecture. It has the latest features to correct and guide itself for in-flight disturbances, DRDP sources added.