ATTACKERS wearing military uniforms have shot dead at least 12 people and wounded 15 in a busy market area in a town in India's restive northeastern state of Assam, an attack blamed by authorities on a regional separatist group.

The gunmen fired indiscriminately and threw hand grenades at the crowded weekly market in Kokrajhar, a town 220 km by road west of the state's commercial capital Guwahati, eyewitnesses said.

One assailant was killed and security forces were in pursuit of three or four others hiding in a nearby forest, Assam police chief Mukesh Sahay told reporters.

Mr Sahay said police had recovered an AK-47 rifle and explosives from the dead gunman, as well as a three-wheeler van the assailants had arrived in.

He blamed the outlawed National Democratic Front of Bodoland (Songbijit) group, a militant outfit fighting for a separate homeland for the indigenous Bodo tribespeople.

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