The eight low-intensity blasts in Goalpara district, which took place on Saturday evening, do not appear to be the handiwork of political groups. In fact, preliminary investigations indicate common criminals are involved, the police say.

The blasts took place between 9.30 pm and 11 pm on Saturday in Goalpara, 200 km west of Guwahati. The first one was triggered near the house of Mainuddin Ahmed, legislator from Jaleswar. "It seems the blasts were triggered by a gang of criminals," said Shyamal Saikia, superintendent of police, Goalpara.

What cinched the matter was the incident at Jaleswar, where three blasts took place. Immediately after the explosions, the villagers caught a motorcycle-borne man. Suspecting he was the one carrying bombs, the villagers lynched him. The man was late identified as Nazrul Islam Khan, a known criminal, from the neighbouring Dhubri district.

"We found a letter on a fake Ulfa letterhead from the spot where he was killed. The letter carried a demand for Rs. 1 crore," said Saikia. The possibility of the involvement of Ulfa was very remote in this case, said Saikia, who has a long experience in anti-Ulfa operation.