The 6.9 magnitude jolt downed power lines, caused walls to crumble and triggered large landslides that blocked roadways.
Relief efforts were hampered by ongoing monsoon downpours, which caused further landslides in the quake-loosened ground across the disaster zone.
Both cell phone and land line service across the affected region were severed by the strong shaking, further impeding relief efforts.
Shaking was felt more than 600 miles away in the Indian capital of New Delhi.
Three people were killed when the wall of the British embassy compound in the Nepalese capital of Kathmandu collapsed, 170 miles to the west of the epicenter.
The initial jolt was followed by two strong aftershocks of magnitude 6.1 and 5.3.
Indian television showed images of wrecked buildings and cracked pavement in Gangtok, the capital of Sikkim state, about 50 miles southeast of the epicenter.
Two major roads were said to have “collapsed” during the temblor. The U.S. Geological Survey said the quake’s epicenter was just inside the border of Nepal, near where its mountainous border with China and India intersect.