Indian security officials on Friday said they had found evidence of attacks planned by Pakistani military-backed militants on a major Hindu pilgrimage in Kashmir.

The security officials said a mine with Pakistan ordinance markings was among caches of ammunition retrieved following intelligence reports of likely attacks on routes used by devout Hindus who trek to the region's holy Amarnath cave every year.

A local government order effectively called off the pilgrimage, asking the pilgrims and tourists to return home.

On Saturday, a senior local government official in Kashmir said the advisory had caused panic and led to the departure of "thousands" of tourists, pilgrims and labourers.

The official did not give a specific number, but he said most of the 20,000 Hindu pilgrims and Indian tourists and the more than 200,000 labourers were leaving the region.

Around 60 international tourists arrived in Kashmir on Saturday, however, the official said. The Indian advisory had cautioned tourists in general but did not give any specific advice to foreign nationals.

Tensions have run high in the mountainous region since a vehicle laden with explosives rammed into an Indian police convoy on February 14, killing 40 paramilitary policemen, and leading to aerial clashes between the two nations.

India accuses Pakistan of funding armed militants, as well as separatist groups in India's portion of the region that are considered non-violent by international observers.

Islamabad denies the Indian accusation, saying it provides only diplomatic and moral support to the separatist movement.

The advisory has left the fleeing tourists and pilgrims disappointed. Kashmir touts itself as a "Paradise on Earth", with Dal Lake - a favourite destination centuries ago for Mughal emperors escaping the summer heat of India's plains - and its famous houseboats, mountains and glaciers a major attraction.

Prabakar Iyer, 45, had travelled to Srinagar from the southern Indian city of Bengaluru on Thursday with his family for a 10-day holiday, but they returned on Friday night.

"I was staying in a houseboat on Dal Lake when the advisory was issued. I fail to understand why we are being asked to leave. Everything is normal here," he said.

Labourer Manjit Singh, a carpenter from the northern state of Uttar Pradesh who has been working in Kashmir for the last nine years, also left.

"I am not afraid but the government advisory has created panic and my family wants me back ... I will return if the situation improves," he said.