The violence near Bagua has left at least 18 policemen dead
Nine Peruvian policemen seized by Amazonian indigenous protesters have been killed during a rescue bid which freed 22 others, officials say.
A further seven were still missing after the military moved to free them from protesters angry at plans to drill for oil and gas on ancestral land.
The hostages were taken on Friday during clashes near Bagua which left at least 22 tribesmen and 11 police dead.
A police official accused the protesters of killing the hostages.
This is the worst violence in Peru since the end of the Shining Path insurgency in the 1990s and the biggest internal challenge faced by President Alan Garcia since he came to power in 2006, the BBC's Americas editor Emilio San Pedro says.
Peruvian police chief Miguel Hidalgo said that the 38 officers had been captured at a petrol facility they were defending in the area about 1,400 km (870 miles) north of Lima, the capital.
"Of the 38, 22 have been rescued by the army, nine have died at the hands of the natives and seven have disappeared," he told Peruvian radio station RPP.
Speaking before the rescue operation, Peruvian Prime Minister Yehude Simon accused the protesters of a "plot against democracy".
He said the 38 policemen had been held hostage by about 1,000 protesters but the army had had them surrounded.
The authorities said there had been five civilian deaths and more than 100 injuries. But indigenous leaders said at least 25 protesters had been killed.
Eyewitnesses in the northern city of Jaen told the BBC they believed the number of dead to be even higher.
Friday's violence erupted as police tried to dislodge protesters from a major road which they had been blocking.
Two months of protests
One indigenous leader, Luis Huansi, told Reuters news agency on Saturday that about 8,500 protesters had taken up strategic positions around the city of Yurimaguas.
The exact number of people killed or injured on Friday is still unknown
He said the protesters would not be using guns: "We are counting on our traditional weapons which our forefathers left to us for defence, weapons to fight. They are spears."
Fuel and transport blockades have disrupted Peru's Amazon region for almost two months, the BBC's Dan Collyns reports from Lima.
Special forces had moved in before dawn on Friday to remove the protesters who were sleeping by the side of the road they had been blockading.
Protesters say the police fired tear gas and live ammunition from helicopters in what was by far the most violent clash in the protests so far.
Alberto Pizango, another indigenous leader, said the protests had been peaceful until the police raid.
"In the 21st Century they continue to kill us indigenous people simply for defending life, our sovereignty over our lands and our dignity," he said after Friday's violence.
But Peru's Foreign Minister, Jose Antonio Garcia Belaunde, told the BBC there were armed men amongst the demonstrators.
He said the government had given the native people 12 million ha (29 million acres) out of the total Amazon territory of around 80 million ha.