The northern and eastern parts of the country were jolted on Sunday after a powerful earthquake hit the Sikkim-Nepal border with a magnitude of 6.8 at 6.10 p.m., leaving at least 17 persons dead and more than 100 injured, besides causing extensive damage to buildings and roads.

The epicentre was about 69 km northwest of Gangtok, 119 km north-northwest of Siliguri and 272 km east of Kathmandu.

The main quake was followed by three significantly high aftershocks — 5.7 at 6.21 p.m., 5.3 at 6.42 p.m. and 4.6 at 7.24 p.m. Senior officials of the India Meteorological Department (IMD) said more aftershocks were likely, considering the magnitude of the quake.

Tremors were felt in Assam, Meghalaya, Tripura, parts of West Bengal, Bihar, Jharkhand, Uttar Pradesh, Rajasthan, Chandigarh and Delhi.

Of the deaths, seven occurred in Sikkim, five in Nepal, three in the Darjeeling hills of West Bengal and two in Bihar, according to reports received here.

Among the victims in Sikkim, two died at Singtham in East district, two in Rishi in West district and one at Mangan in North district, Chief Secretary Karma Gyatso said in Gangtok. Two army jawans were killed in north Sikkim, and three army vehicles including one with army personnel were reported missing, army officials said in Delhi.

Two buildings of the Indo-Tibetan Border Police (ITBP) collapsed in the Pegong area in north Sikkim, a senior official said.

Official sources said the casualties could go up as the affected areas were in remote areas and there was not much information flowing in. In Sikkim, there were also reports of landslips as it was raining, and power supply was seriously disrupted. Mobile phone services were not functioning and only BSNL lines were working.

Several buildings developed major cracks in the State and disaster management personnel were deployed, Mr. Gyatso said.

In Nepal, three of five deaths occurred outside the British Embassy in Kathmandu when a high brick wall collapsed.

A report from Bihar said an NTPC plant at Bhagalpur was shut down immediately after the quake as a precautionary measure. In the State, the two deaths, of a five-year-old girl and a youth, occurred in Nalanda and Darbhanga districts

Following the disaster, Prime Minister Manmohan Singh called up Sikkim Chief Minister Pawan Kumar Chamling and offered all Central assistance. He directed Cabinet Secretary Ajit Kumar Seth to call an emergency meeting of the National Disaster Management Authority.

“The Prime Minister himself is monitoring the developments connected to the quake,” said Mr. Seth.

It has been decided to send four IAF aircraft to Bagdogra in West Bengal — two from the Hindon airbase, one from Palam and another from Kolkata — with personnel of the National Disaster Response Force equipped with all equipment. From Bagdogra, the personnel will be taken to Gangtok by road. This is being facilitated by the Border Security Force and the West Bengal Government, an official release said.

The Army has started relief operations and a large number of civilians have been accommodated in army areas in Gangtok, Darjeeling and Kalimgpong.

After the earthquake, the Siliguri-Gangtok road has been blocked and 10 Army Engineering columns have been deployed to open it for moving rescue and relief and other engineering equipment to the region.