At least five people were confirmed dead in a strong earthquake which hit the northern Indian state of Sikkim on Sunday evening, said local TV reports.

Four people died in Sikkim and one in the eastern state of Bihar in the quake-related accidents.

In neighboring Nepal, at least five people were killed in the quake, including three at the British embassy in Kathmandu where a building reportedly collapsed.

More information is being awaited after the primary reports of casualties from the strong earthquake measuring 6.9 on the Richter scale which struck at 6:11 p.m. local time (12:41 GMT) with its epicenter in the India-Nepal border area or 68 km northwest of Sikkim's capital Gangtok.

Mudslides are reportedly blocking roads between India and Nepal in western Sikkim, making rescue efforts difficult, said the local authorities.

While telephone communications have been greatly cut, there are reportedly many injuries, especially women and children, during the shock, according to private phone calls with the disaster- stricken areas by local Sikkimese community in Delhi.

Some aftershocks and landslides hit Sikkim and neighboring areas Sunday evening while local authorities have sent police to the streets of Gangtok to maintain peace and order.

Meanwhile,some 200 rescuers are heading to Sikkim and its neighboring areas from other parts of India, while the Indian Air Force is sending five planes to join rescue operations.

Indian Prime Minister Manmohan Singh immediately convened a meeting of the National Disaster Management Authority and called Sikkim chief minister Pawan Kumar Chamling to express his full support.

The Indian Air Force flew five cargo planes with relief material and rescue personnel for deployment in West Bengal and Sikkim, said Indo-Asian News Service.

The dead in Sikkim included a child, an official with a pharmaceutical company who died when a house collapsed, and a man whose vehicle was trapped in a massive mudslide on the outskirts of Gangtok, said the news service.

An earlier TV report said an army soldier died in the earthquake related accidents.

The strong tremor jolted buildings across northern and eastern India, including Delhi, Uttar Pradesh, Uttarakhand, Jharkhand, Bihar, West Bengal, Assam and Mizoram,prompting people to run out of their homes in panic.

Power supply was disrupted in parts of northern West Bengal, Chief Minister Mamata Banerjee said in Kolkata.

The paramilitary Border Police of India has launched search and rescue operations in Pegong area of north Sikkim which has been "badly affected" with two of their buildings collapsing in the quake, said Press Trust of India.

Earlier, an earthquake measuring 4.2 on the Richter scale had shaken north India on Sept. 7 with its epicenter near Sonepat in Haryana, 65 km from New Delhi.