An Indian mountaineer and a CIA expert have come out with an authoritative account of how nuclear devices were planted atop high Himalayan peaks to monitor Chinese nuclear tests in the 1960s.

In an explosive book Spies in the Himalayas, mountaineer Capt Mohan Singh Kohli, who led these expeditions to Nanda Devi, Nanda Kot and other summits between 1965 and 1968, and CIA expert Kenneth Conboy chronicle the planting of nuclear-powered monitoring devices by the CIA.

This was a time when there were no satellites to monitor such developments.

One of the devices, which could not be planted atop Nanda Devi summit due to bad weather and was left cached on the mountain for the next expedition, went missing.
 
This caused serious concern about possible radioactive contamination of the environment and, in particular, of the River Ganges.
 
Repeated searches could not retrieve the device which still remains missing, the book, published by Harper Collins, says.

This highly sophisticated and top-secret mission was kept under wraps for 38 years, barring a "partial and inaccurate leak" made to a US magazine in 1978, which rocked the Indian Parliament.

The then foreign minister Atal Bihari Vajpayee had declared in London on April 30, 1978 that India would recover the missing nuclear device.

Kohli also participated in the famous sailing expedition, 'Ocean to Sky', in 1977 on the Ganges against the currents. The expedition, led by Sir Edmund Hillary, was meant to monitor possible radioactive contamination caused by the missing nuclear device.

The book contains several interesting details about these expeditions and the US plans to install the nuclear devices, like the unauthorised climbing of Nanda Devi twice, capture of an Indian Special Frontier Force commando by the Chinese in Tibet, the appearance of an American spy plane U-2 in India on a secret mission, use of the world famous Huskie aircraft for high-altitude search and Kohli's seven close brushes with death.