At least 27 people killed and over 100 injured in Sikkim, West Bengal and Bihar in a 6.8 magnitude earthquake last evening. The epicentre of the quake – the biggest in two decades, was located at Mangan and Sakyong areas, over 50 kilometres from Gangtok on the Sikkim-Nepal border. The quake claimed 16 lives in Sikkim, 4 in West Bengal, and 7 in Bihar. The quake also claimed five lives in neighbouring Nepal. Tremors were also felt in Assam, Meghalaya, Tripura, Jharkhand, Uttar Pradesh, Rajasthan, Chandigarh and Delhi.Two Army jawans were among those killed in North Sikkim area and three army vehicles including one with army personnel were reported missing, army official said in Delhi. AIR Gangtok correspondent reports that several roads have been blocked at many places in Sikkim following landslides. Chief Secretary of West Bengal Samar Ghosh said that three persons died in Darjeeling district and one in Jalpaiguri district.In Bihar, three members of a family were killed at Sherghati in Gaya District of the state following collapse of roof of their house. Two persons killed in Patna and Nalanda districts as wall of their houses fell on them. In another incident, two people died in stampede while running for safety during earthquake in Darbhanga and Bhagalpur districts. The State Government has issued orders to alert all police stations, Block Offices, Hospitals and National Desaster Reforms Force (NDRF) teams in view of earthquake. Chief Minister Nitish Kumar has announced 1,50,000 compensation for the kin of those killed in earthquake.At least five people were killed in Nepal, three of them outside the British Embassy in Kathmandu, when a high brick-wall collapsed.Following the emergency meeting of the high level crisis management committee in New Delhi late last night, Cabinet Secretary Ajit Seth said that the rescue operations had started in the affected areas. The Centre rushed four teams of National Disaster Rescue Force from New Delhi and another five from Kolkata to Sikkim. The teams comprise 40 members each who are expert rescuers. Quoting defence sources, AIR Correspondent reports, five Indian Air Force aircraft have been pressed into service for rescue operations carrying personnel of National Disaster Rescue Force (NDRF) along with equipment for rescue measures.Meanwhile, army medical teams have reached the forward areas along the China border to provide treatment to the villagers and instill confidence in them. The Indo-Tibetan Border Police has launched search and rescue operations in Pegong area of north Sikkim and rescued about 200 people. ITBP spokesperson Deepak Pandey told our correspondent that two ITBP buildings collapsed after the state was rocked by the earthquake. The 9th NDRF battalion based in Bihta, Bihar has been requisitioned for relief work in Sikkim.The Prime Minister Dr.Manmohan Singh spoke to the Sikkim Chief Minister Pawan Chamling and offered all help.Congress President Mrs. Sonia Gandhi has expressed deep concern and anxiety over the earth quake. She has urged the disaster management team to remain vigilant and extend all help in the affected areas.