Ulfa rebels want the military campaign against them stopped

The police suspect the attacks are the work of the United Liberation Front of Assam (Ulfa).

Seventy Hindi speaking migrants were killed in a week of attacks in northern Assam at the beginning of January.

Ulfa is fighting one of India's longest running insurgencies to establish an independent homeland in Assam.

The rebels say India's central government exploits the state's rich resources such as tea and natural gas and does little for its people who are ethnically closer to Burma and China than to India.

A police spokesman said a powerful explosion late on Sunday near a crowded vegetable market in Barpeta district killed a cobbler and injured five other people - one of whom died later.

Earlier two people were wounded when a bomb exploded outside a railway station in the state.

On Saturday, the rebels shot dead a village councillor from the Congress party near the oil town of Digboi, police said.

Two weeks ago, thousands of soldiers were ordered to fan out across Assam in search of Ulfa rebels blamed for the deaths of at least 70 people.

An Ulfa commander has said his fighters would now start killing leaders of the state's ruling Congress party unless the Congress government in Delhi stopped military operations against the group.