India has test-fired its longest-range nuclear-capable ballistic missile, Agni-III, officials said.

The surface-to-surface missile was test-fired off the coast of Orissa state in eastern India.

With a range of more than 3,000km (1,865 miles), the missile could hit targets as far off as Beijing and Shanghai, analysts say.

The Agni-III is India's most sophisticated long-range missile. It was successfully test-fired last year.

The first attempt to test the missile in July 2006 failed after it developed a snag during the flight and came crashing down into the Bay of Bengal.

The missile was re-configured for the second launch in April 2007.

Boost capability

Indian defence spokesman Group Captain Ramesh Kumar Das said the latest test was launched from the interim test range at the Wheeler's Island in the Bay of Bengal.

The intermediate range ballistic missile is capable of carrying a 1.5-tonne nuclear payload.

When deployed, it will boost India's second-strike capability as it can be launched from anywhere using a mobile launcher.

It will need a few more tests before it can be inducted into the armed forces, Group Captain Das said.

Possession of the Agni-III will give India deep strike capability because it would have Chinese cities like Beijing and Shanghai and the US island base of Diego Garcia in the Indian Ocean well within its striking range.

The Agni-II missile, already tested and deployed, has a range of 2,000km (1,243 miles).

The Agni-1 has a range of 750km (466 miles).

The Agni (literally "fire" in Hindi and Sanskrit) missile family is believed to be the mainstay of the Indian missile-based strategic nuclear deterrence, Group Captain Das said.

He said the Agni family would continue to expand its stable, providing a breadth of payload and range capabilities.