The death toll from the 6.8-magnitude earthquake that struck north-eastern India has claimed 21 lives as rescue work picked up in the region Monday, officials said. The epicentre of Sunday's quake was 68 kilometres north-west of Gangtok, the capital of the Indian state of Sikkim, which is situated in the eastern Himalayan range. The death toll in the state had risen to 15 with the recovery of more bodies during rescue operations overnight, an official at the police control room in Gangtok who requested anonymity said. Six deaths were also reported from the eastern states of Bihar and West Bengal, the CNN-IBN network reported. At least 150 people were injured, 60 of them in Sikkim, the network was quoted as saying by the German Press Agency "DPA".