Rivals kill 37 tribals in Assam

In the first attack, 22 people were hacked to death and their dismembered bodies burnt by the rival Dimasa tribe.

Police said more than 60 people were wounded in the attack in the Karbi Anglong district of the tea-and-oil rich state.

In another attack, the Dimasa tribesmen attacked a Karbi village, killing 15 people and burning around 60 mostly bamboo and straw houses.

"Heavily armed Dimasa militants stopped two packed buses, pulled out the victims, hacked them to death and then threw their bodies into the burning buses," police officer Pankaj Sharma said from Diphu some 240 km from Guwahati.

"After the second attack Dimasa militants forcibly took away many villagers to a nearby jungle and they are still missing," he added.

The Karbi and Dimasa have been fighting for years over land in Assam, home to several dozen tribal and ethnic groups and separatist and tribal militant outfits.

In the past two weeks, at least 72 people have been killed in ethnic violence, a majority of them Karbis.

"Additional troops have rushed to the area to control the situation and rescue kidnapped villagers," said Himata Biswa Sarma, Assam state's official spokesman.

More than 500 tribals have become homeless in the bloody clashes and many of them have taken shelter in government buildings and schools.

India's northeast, comprising seven states, is home to more than 200 tribes and ethnic groups and is circled by China, Bhutan, Bangladesh and Myanmar.

The region has been racked by separatist and tribal insurgencies for more than 50 years.