A 5.1-magnitude earthquake on Saturday struck Nepal at 11.30 a.m. with its epicentre at Barpark in Gorkha district, seismologist Mukunda Bhattarai from the National Seismology Centre (NSC) said.This is the third quake with its epicenter in Gorkha after the deadly tremor on April 25. A series of tremors and aftershocks have struck the Himalayan nation in the last one week and has made it difficult for the people to return to thier houses. According to the data provided by the home ministry, the temblor has so far claimed over 6,500 lives.