Another three mountaineers have died on Everest, expedition organisers and officials said Friday, taking the toll from a deadly week on the overcrowded peak of the world’s tallest mountain to seven.

Nepal has issued a record 381 permits costing $11,000 each for this year’s spring climbing season, triggering bottlenecks en route to the summit after poor weather cut down the number of climbing days.

“Two more Indian climbers have died on Everest yesterday,” Mira Acharya, spokeswoman for Nepal's Tourism Department, told AFP, while expedition organisers confirmed the third fatality.

Kalpana Das, 52, reached the summit but died on Thursday afternoon while descending, as a huge number of climbers queued near the top of Mount Everest.

Another Indian climber, 27-year-old Nihal Bagwan, also died on his way back from the summit.

“He was stuck in the traffic for more than 12 hours and was exhausted. Sherpa guides carried him down to Camp 4 but he breathed his last there,” said Keshav Paudel of Peak Promotion.

An Austrian climber died on the northern Tibet side of the mountain, his expedition organiser said.

The 65-year-old died close to the summit on his descent.

Wednesday saw an Indian and American climber die on the mountain. Last week, an Indian climber died and an Irish mountaineer is presumed dead after he slipped and fell close to the summit.

Ang Tsering Sherpa, former president of the Nepal Mountaineering Association, said that the weather window to summit this season was narrow, meaning that many teams were still waiting to go up.