New Delhi - At least four people were killed by a car-bomb in India's north-eastern state of Assam Monday, news reports said.

More than 20 people were wounded in the explosion that occurred in the crowded market area in the Maligaon suburb of state capital Guwahati, the NDTV network reported.

Several cars and shops caught fire following the bombing and fire tenders were rushed to the area to douse the blaze, the report said.

Authorities said they suspected Assam's biggest separatist outfit, United Liberation Front of Asom.

The ULFA which has been fighting for an independent homeland since 1979, marks its 30th Raising Day on Tuesday.

India's north-east, which shares borders with China, Myanmar and Bangladesh, is a volatile region where nearly 40 separatist, tribal or leftist groups are active in five states.

More than 15,000 people have lost their lives to insurgency in the region in the past decade. dpa