16,000 Tons Of Rock Slide 500 Feet Down Yosemite Cliff, Some Into Hetch Hetchy Reservoir

YOSEMITE NATIONAL PARK (CBS/AP) -- Officials at Yosemite National Park say a massive amount of rock has fallen from a cliff, closing a hiking trail.

The National Park Service said Monday that nobody was hurt when the 16,000 tons of rock fell 500 feet from a cliff near Hetch Hetchy Reservoir on March 31. Many boulders tumbled into the water.

Officials say the rock crashed down from a cliff east of Wapama Falls. The rock broke into numerous boulders, crushing trees and sending up a small dust cloud.

Some 400 feet of the Rancheria Falls Trail were destroyed and park staff says it will remain closed for now. Park officials say hikers can still get to Wapama Falls starting at O'Shaughnessy Dam.