By Subir Bhaumik
BBC News, Calcutta
Separatist rebels have killed seven personnel of India's Central Reserve Police Force (CRPF) in the north-eastern state of Assam.
Police said members of the Dimasa tribe attacked the CRPF convoy near Bihangi village in North Cachar Hill district.
A senior CRPF commandant, who was travelling as part of the convoy, escaped unhurt.
Assam is one of India's most volatile states where several groups are fighting against Indian rule.
"The rebels fired heavily from both sides of a hill road, hitting the last two vehicles in the convoy," an Assam police official told the BBC.
He said seven CRPF men were killed on the spot, several others were injured and the rebels managed to carry away a few weapons.
The commander of the 50th CRPF battalion, B Chetri, who was travelling with the convoy from their headquarters in Halflong to a remote location near Bihangi, escaped unhurt.
Intelligence officials have blamed the attack on the Black Widow, a rebel group of the Dimasa tribe.
They say it is the only armed group active in the North Cachar Hills now.
A senior leader of the group was arrested by the security forces a fortnight ago and officials say Friday's attack could be in retaliation against the arrest.
The group has regularly attacked settlers from non-tribal communities from elsewhere in India as well as the security forces.
In the last two years, these rebels have killed more than 50 people.