Steck, Italian Simone Moro and Jonathan Griffith from Britain were proceeding to Camp 3 from Camp 2 on the west face on Saturday when the incident happened.
“It can get a bit heated on the mountain, but I’ve never experienced anything like this,” Steck told the Blick tabloid.
Steck said he was hit by a stone and was also punched.
“Another climber got between me and the attackers. Otherwise I would not be alive. I was afraid for my life and that of my colleagues,” Steck said.
The Swiss extreme mountaineer was on his 16th Everest expedition.
At a height of about 7,200 metres he and his team came across a group of guides mending ropes on the Lhotse face.
The climbers moved 50 metres to the right to avoid them, Steck told Blick.
An argument broke out, with the sherpas accusing the Europeans of stepping over their ropes and triggering a fall of ice.
Retreating to Camp 2, the climbers were met by an angry group of 100 sherpas who kicked and punched them. Steck was injured on his mouth.
“They told us clearly that if we spent the night at the camp, one of us would be dead in the morning,” Steck said.
Nepalese police are reported to have detained three ringleaders.