A bomb exploded in a train coach in India's insurgency-hit northeast on Tuesday, killing at least three people and injuring another 29, a state government official said.
The explosion occurred shortly after the train arrived at Diphu railroad station, about 200 miles south of Gauhati, the capital of Assam state, said District Magistrate M.C. Sahu.
The train was heading from Lumding in central Assam to the eastern commercial hub of Tinsukhia, Sahu said.
Tuesday's blast comes just days after suspected Muslim militants attacked targets across Mumbai, killing at least 172 people and injuring 239. Tuesday's blast was not seen as related to the Mumbai attacks.
Two train passengers were killed on the spot and one of the 30 wounded later died in a hospital, said Bhaskar Mahanta, a police official. Two of the wounded were in critical condition.
The bomb was a timed device, left in a bag on an overhead rack of the train coach and it blew off a part of the roof, said another police official, K.K. Sharma.
While no one immediately claimed responsibility for the attack, Sharma said an ethnic insurgent group, Karbi Longri National Liberation Front, fighting for wide autonomy in the state for the past five years, was suspected.
The front is one of the three groups active in the region; the other two groups have reached cease-fire accords with the government.
Separately, suspected insurgents shot and killed two migrant workers in the same district on Tuesday, Mahanta told The Associated Press.
The two petty traders from northern India were pulled out from their homes in Dolamara, a village, and fatally shot, he said, blaming the same insurgent group, Karbi Longri National Liberation Front.
Suspected separatists have killed nearly 300 migrants over the past three years in Assam state. They have been targeting thousands of Hindi-speaking migrants from northern states like Bihar and Uttar Pradesh who they claim usurp the local population's job opportunities.
In October, the state witnessed 13 coordinated bomb attacks, which killed 89 people and wounded more than 800 in four towns.
Several insurgents groups are battling for power, for ethnic pride and for control of drug routes in India's northeast, an isolated collection of seven states and hundreds of ethnic groups and subgroups. They fight the government and they fight each other in a region crippled by poverty and political chaos.