Guwahati, Dec 10 (IANS) At least four people were killed and 17 others injured, six of them critically, when a powerful bomb blast ripped through a crowded marketplace in a Assam town Thursday, police said.

The blast took place at a daily market at Missamari town in Sonitpur district, about 220 km north of state's main city of Guwahati, a police spokesman said.

'The market was teeming with people when the bomb went off, leading to utter panic and chaos in the area,' district police chief Jitmol Doley said.

Witnesses and police officials said four people died on the spot and at least 17 were wounded.

'The condition of at least six of the injured is stated to be critical with their limbs separated from the body and stomachs ripped apart,' Abhir Das, a businessman in the area, said.

The blast site is close to a police station and an army base camp.

'The injured were shifted to local hospitals,' Doley, the police chief, said.

Police blamed the outlawed National Democratic Front of Bodoland (NDFB) for the attack.

'We strongly suspect the hand of NDFB in the blast as the area is a stronghold of the outfit and there were reports of militants serving extortion notices to the local people during the past few days,' an intelligence official said.

The NDFB is a rebel group fighting for an independent homeland for the Bodo tribe in Assam.

The NDFB is blamed for the Oct 30 serial explosions in 2008 that killed about 100 people and injured more than 400.