GUWAHATI, India: At least 11 people have been killed in clashes between police and tribal groups opposed to ongoing local elections in India's northeastern state of Assam, police said on Tuesday.

"The situation is very critical and so far we have reports that 11 people are dead and about six are injured," Bhupen Bora, a senior police official, told AFP.

The clashes were reported in Goalpara around 120 kilometres (75 miles) from the state's main city Guwahati.

Bora said nine of the dead were killed in police firing when two tribes opposing the elections started torching villages and attacked government officials.

"The Rabha and Hasong tribes want autonomy, they reject government rule in the district," said Bora.

Northeast India has seen decades of friction among ethnic and separatist groups, although some rebels have recently started peace talks with the government.

More than 10,000 people have lost their lives to unrest in the the tea- and oil-rich state of Assam over the last two decades.