Shimla: The Indian Air Force (IAF) on Friday resumed its rescue operation on the fourth day and airlifted 81 people, including six foreigners, from Himachal Pradesh's snow-marooned Lahaul Valley.

The rescue operation was hampered in the afternoon owing to the onset of snowfall in the high hills.

Over 1,000 persons, including 30 foreigners, have been rescued since September 24. Out of these, 211 were airlifted and the remaining evacuated by road via under-constructed Rohtang tunnel, an official statement said.

Most of them were stranded at various locations in the Himalayas for the past six days with heavy snowfall in the region triggering massive landslides that snapped road links in the Lahaul-Spiti district.

Snow clearing operation by the Border Roads Organisation (BRO) to restore the road link between the Baralacha Pass and district headquarters Keylong is in full swing.

It was estimated that nearly 500 tourists and truckers were still stranded near the Baralacha Pass.

Another large group was reported to be stuck in Suraj Tal Lake and Zingzing Bar areas along the Keylong-Leh road.

Chief Minister Jai Ram Thakur held a meeting here to review the ongoing rescue operation by the district administration, the IAF and the BRO.

An official statement quoting the Chief Minister said the road up to Baralacha Pass would be cleared by Friday evening.

He said all rescued people are being taken for medical examination. Efforts are being made to restore the communication network in the Lahaul valley.

Thakur said during the monsoon the state suffered a loss of about Rs 1,479 crore and in the last four days the state suffered Rs 220.29 crore loss.

The Central government has released Rs 122 crore as the first instalment for undertaking immediate rehabilitation measures, he said.

Water supply to Manali and Keylong towns has been restored and till the electricity supply was restored in the Lahaul valley, efforts would be made to provide solar lamps and lights to the people.

Two light utility helicopters were additionally deployed on Thursday along with three IAF choppers, including MI-17, to speed-up the rescue in Lahaul.

Early snowfall in the higher reaches, cloudburst and heavy rain devastated large parts of the state from September 22 to 24.

Heavy snowfall on the Rohtang Pass (13,050 ft) has cut-off the Lahaul and Spiti Valleys, affecting a large number of tourists and hampering water and electricity supply.