By Subir Bhaumik BBC News, Guwahati |

 Houses set on fire in Karbi Anglong district (photo by P Sainee) |
Security forces in the north-eastern state of Assam have been told to shoot on sight after tribal clashes claimed 34 lives in the past two days. An indefinite curfew is also in force in Karbi Anglong district, where violence erupted late on Sunday.
In one attack, Dimasa tribal militants massacred 22 members of the rival Karbi tribe, eight of them women, police say. Another 12 Karbis were killed later.
The two tribes have a long history of feuds over territory in the state.
Set alight
Police officials told the BBC that 22 people belonging to the Karbi tribe were dragged out of two passenger buses and killed at Jirikidhing in Karbi Anglong district on Sunday.
In another incident, 12 more Karbis were killed when the Dimasa militants attacked Saraim, a Karbi village, just after midnight.
The attackers used guns and sharp weapons to kill the Karbis, police said.
More than 130 houses have also been set on fire by the militants in different parts of the district since the violence began.
The Indian army has stepped up its troop deployment in the troubled district to keep the peace.
Nearly 70 people have died since clashes between the Dimasas and the Karbis started in early September.
Assam is home to more than 30 major tribes and feuds between militias claiming to represent them over conflicting homeland demands are fairly common.