Nanga Parbat. Photo: Guilhem Vellut CC-BY-SA-2.0

Expeditions to the world’s ninth highest mountain have been suspended after 11 climbers were shot dead by a group dressed as security forces.

The Pakistan Taliban said an offshoot faction of its organisation, Junood ul Hisfa, carried out the murders in retaliation for western drone attacks in the country.

The mountaineers were killed on Sunday at the Diamir base camp of Nanga Parbat, the westernmost peak of the Himalaya and, at 8,126m (26,660ft), one of the world’s 14 highest, 8,000m mountains.

The dead climbers were from Ukraine, Lithuania, Slovakia, Nepal and two Chinese plus a Chinese-born US citizen. A Pakistani guide also died in the attack in Baltistan in the North of Pakistan.

The region had previously been a haven of peace for mountaineers in an otherwise turbulent country.

The British Mountaineering Council said it believed the mountaineers were in seven teams, all intending to climb Nanga Parbat by the Kinshofer Route on the northern Diamir face of the mountain. It said an eighth, a team from Romania, was climbing from the southern, Rupal, side and was not involved in the attack.

All climbers in the Diamir area were escorted by the Pakistan military to Gilgit and many have since travelled on to Islamabad.

A ban on climbing in other areas of Pakistan, including K2 in the Karakorum, is being considered by authorities.

Lindsay Griffin of the BMC said: “An unprovoked attack of this magnitude on a mountaineering base camp seems unprecedented, and makes previous incidents, such as the famous Sendero Luminoso assault on a base camp in the Cordillera Huayhuash during the 1980s, seem almost tame by comparison.

“However, last year’s incidents, including a Taliban attack on a bus in a nearby area when 20 passengers were killed, show strong presence of terrorists in this region.”