A huge rescue operation is underway in the Hindu Kush.

This is the Salang Pass in Afghanistan.

It's the main route across the mountains from Kabul to the north of Afghanistan.

The landmark Salang road tunnel has been closed by a series of avalanches after days of heavy snowfall.

Scores of people are believed dead after spending Monday night in extreme mountain conditions. It's estimated about three thousand were trapped in their vehicles, leading to the massive recovery effort.

Afghan defense minister, Abdul Rahim Wardak.

[Abdul Rahim Wardak, Afghan Defense Minister]: (Dari)
"The most serious avalanches were in south of Salang Pass and have affected around 3,000 of our people, a number of them are either wounded or lost their lives."

About six hundred soldiers and emergency workers are involved, as the operation goes into a second night. Some of the bodies of the dead were being carried by luckier passengers who managed to walk out of danger.

It's believed hundreds remain trapped.

President Hamid Karzai says he's saddened by the deaths and has ordered all possible effort to re-open the pass.