A dozen bombs exploded in quick succession around the northeastern Indian state of Assam yesterday, killing 61 people and injuring at least 300 in the worst such attack in the restive region since independence in 1947.

Some local officials said that the bombs, which exploded within an hour of each other, could be the work of the United Liberation Front of Asom (ULFA), which has been fighting for an independent homeland in Assam since 1979.

The rebel movement, however, denied any involvement in the blasts, six of which hit the state capital, Guwahati, with six others striking western districts of Assam.

ULFA leads just one of many separatist movements that have led to the deaths of more than 50,000 people in India’s northeastern areas. Indian officials say that Islamist militants from neighbouring Bangladesh are also active in the region.

“This is an act of cowardice, designed and carried out to spread terror,” said Tarun Gogoi, the Chief Minister of Assam. “Our intelligence did have prior information about the blasts but we weren’t expecting it to be such a serious incident. As for now, we are not ruling out an ULFA hand behind these blasts.”

An immediate curfew was imposed in Guwahati as angry residents went on the rampage, attacking police vehicles and public buses and burning auto-rickshaws.

One of the bombs exploded in front of the Guwahati District Magistrates’ Court, killing five people. “I had gone to the market to buy vegetables when I heard a deafening sound,” said S.K. Dutta, an eyewitness. “People were running across madly, there was thick black smoke in the air and vehicles were burning. It was complete chaos.”

Television footage showed firefighters spraying the wreckage of cars and motorcycles while bystanders dragged the wounded to cars and police covered the burnt remains of the dead with white sheets.

The synchronised attacks came six weeks after a series of bomb blasts in popular shopping areas of Delhi, the Indian capital, left more than 20 people dead and hundreds injured.

An Islamic group calling itself the Indian Mujahidin has claimed responsibility for that attack and for several others recently, raising fears of a new, homegrown terrorist threat to India.

Last month there were clashes in Assam between members of the indigenous Bodo tribe and Muslim settlers that left at least 47 people dead. Indian troops also killed seven militants from a Bangladesh-based Islamist group in Assam.

Assam’s Health Minister, Himanta Biswa Sarma, the Government’s main spokesman, said preliminary investigations showed that some of the bombs had been strapped to bicycles and packed with incendiary material to trigger fires.

“The needle of suspicion is on the ULFA,” he told reporters. “Most of the bombs were planted in crowded places like markets and office complexes. So it shows that the perpetrators wanted high casualties.”

However, ULFA condemned the attack and offered its condolences to the victims of the blasts. “The ULFA is in no way involved in the blasts,” said an e-mail statement signed by Aanjan Borthakur, of the group’s central publicity unit.

ULFA has been fighting for an independent Assam since 1979, accusing the federal Government of plundering the region’s tea, timber and oil resources while neglecting basic infrastructure and services.

Now wedged between Bangladesh, Bhutan, China and Burma, Assam was an independent kingdom for more than six centuries until its conquest by the British in 1826.

When India won independence it was one of the country’s three wealthiest regions. Today it is one of the three poorest states, even though it produces more than half of India’s tea and 17 per cent of its oil.

ULFA began peace talks with the Government in 2006 but they fell apart after six weeks and both sides resumed a conflict in which more than 10,000 people have now been killed.

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