By Charles Haviland
BBC News, Everest region
Trekkers and climbers are being searched at checkpoints
A specialist doctor working in the Everest region of Nepal has warned there will be a "catastrophe" when the world's highest mountain reopens.
Under China's pressure, Nepal has closed communications and movement in base camp and higher until the Olympic flame reaches the summit through Tibet.
The base camp is full of frustrated climbers waiting to get to the peak.
The doctor says he fears disaster may strike during the rush to climb Everest once it reopens.
The high-altitude physician, who did not want to be named, told the BBC he was worried that many climbers were unable to prepare their bodies for extreme altitudes with practice sorties as they would usually do.
Once the mountain was reopened after the torch's departure, there would be a congested rush to reach the top, he said.
He voiced concern at what might happen if a storm blew in.
"You're going to have weak climbers who are not acclimatised stuck very high on the mountain," the doctor said.
"And we could have potentially the worst disaster in Everest's history because of those conditions."
A dozen more Nepalese soldiers were seen moving towards base camp on Tuesday.
In the camp, the security forces have confiscated all communications equipment and imposed a news blackout.
The doctor said he had already treated many members of the military who had fallen sick because of the altitude.
Nepal says it has closed the mountain to oblige its ally and helper, China.