Nuclear belligerence: A history of close calls

Sixty years ago, the United States and Soviet Union brought the world to the brink of an atomic war over Soviet missiles deployed on the island of Cuba.

AFP looks back at other nuclear near misses:

The 13-day showdown between US President John F Kennedy and Soviet leader Nikita Khrushchev has been documented in great detail.

But one incident only came to light many years later.

On October 27, 1962, just as the crisis was nearing resolution, one of four Russian submarines sent to the area with nuclear torpedoes aboard found itself targeted by the US Navy after getting stuck in the Sargasso Sea.

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When US forces began dropping non-lethal charges to pressure submarine B59 to surface, the frazzled crew, which had Moscow's green light to use the vessel's "special weapon" in event of attack, thought war was breaking out.

Believing that "the point of no return" had been reached the submarine commander decided to launch the torpedo but he needed the agreement of two other officers, including the second-in-command Vasily Arkhipov, according to the Russian defence ministry's "Army Legends" documentary series.

Arkhipov kept his composure and opposed the launch, guessing correctly that the Americans did not know the submarine was carrying a nuclear weapon. The man "who prevented World War III" died in 1998.

Another level-headed Soviet officer helped prevent a potential nuclear conflagration 20 years later.

On September 26, 1983, Air Force Colonel Stanislav Petrov was on duty at a secret base near Moscow responsible for monitoring missile attack early warning systems when the alarms started ringing.

Petrov had just minutes to react to a warning that five American intercontinental ballistic missiles were headed towards the Soviet Union.

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With Soviet nuclear doctrine calling for retaliation, reporting it to his higher-ups would have had enormous consequences.

But Petrov's gut instinct told him that an American attack would have involved around 100 missiles and he correctly deduced it was a false alarm.

Soviet experts later concluded that the warning system mistook the sun's reflection off clouds for a missile.

Petrov was decorated several months later but the incident was covered up for a decade.

In May 2002, India and Pakistan, at odds over the disputed Himalayan state of Kashmir since their partition in 1947, went to the brink.

India blamed Islamists from Pakistan for a suicide attack against the parliament in New Delhi on December 13, 2001, that left 14 dead.

The two countries, which became nuclear powers in 1998, mobilised a million soldiers along their shared border.

In April 2002, Pakistani President Pervez Musharraf declared he would use nuclear weapons if threatened with destruction by an attack from India.

India's defence minister George Fernandes was scathing, saying: "India can survive a nuclear attack, but Pakistan cannot."

New Delhi and Islamabad carried out months tit-for-tat missile tests before agreeing to US-sponsored de-escalation measures that lead to a ceasefire in November 2003 and leaders' talks in January 2004.

In 1988, a KGB defector, Colonel Oleg Gordievsky, revealed that Soviet leaders had nearly pressed the button five years earlier in November 1983, when they believed the West was preparing a surprise nuclear attack on the Soviet Union.

The panic attack was sparked by NATO manoeuvres.

On January 25, 1995, aides brought Russian President Boris Yeltsin his nuclear briefcase when Russian radars mistook the launch of a Norwegian meteorological sounding rocket from the Arctic Circle for a US strike.

Yeltsin concludes that it is not actually a US missile and does not retaliate. A week later Moscow admits there was a "misunderstanding".