Police said 29 officers had survived, but 37 others were still missing after the rebels fired from hilltops at their boat passing through a gorge in Orissa state's Malkangiri district.

The anti-insurgency unit was looking for rebels in their jungle stronghold when they were attacked, police said, adding that many of the officers jumped into the water.

"The search operation is on, both in the water and in the nearby forest," said police officer Sanjib Patnaik. "Military and police are using helicopters, but they did not spot any dead bodies yet."

Indian media quoted witnesses as saying that the Maoists used grenades and rockets to ambush the vessel, a claim that police denied.


Rescue workers said some policemen could have been trapped in the boat and drowned.

Agencies