Ice block stalls hundreds of Everest climbers at base camp

Officials assessing route after serac between base camp and camp one deemed unstable and too risky for climbers

A large ice block on the route just above the Mount Everest base camp has forced hundreds of climbers and local guides to delay their attempt to scale the world's highest peak.

The serac between base camp and camp one is unstable and is risky for climbers, said Himal Gautam of Nepal's department of mountaineering on Friday.