Are you sure is 'bandito'? Are you sure?"

American pilot speaking to Peruvian pilot

On the tape, from a CIA drug surveillance plane, the American crew express doubts that the missionaries' plane was on a drugs flight, but they did not explicitly try to stop the Peruvians until the shooting began.

"No! Don't shoot! No mas! No mas!," one of the US pilots shouts in broken Spanish after the plane, a Cessna, is fired at.

Guidelines ignored

The shooting down of the Cessna was caused by language mix-ups, errors in procedure and poor communication, holding up the flow of information, the inquiry said.

The investigation team, led by US Assistant Secretary of State Rand Beers and Peruvian Air Force Major-General Jorge Kisic Wagner, did not assign blame.

But they said guidelines developed by both governments to prevent such an occurrence had been ignored.

Missionaries say the plane filed a flight plan

"There is no direct blame here," General Kisic said.

"To us, the system has had a series of weaknesses that we have to strengthen so that these very unfortunate events do not occur again."

The missionaries' plane was first spotted by a US drugs surveillance aircraft carrying a CIA-hired crew.

Despite their reservations, they informed the Peruvian authorities of the Cessna's location.

Peruvian officers on the ground said they were unable to locate a flight plan for the plane, so they sent up an A-37 jet that flew near the Cessna.

Because the plane apparently ignored orders to land, the Peruvian jet opened fire.

Pilot Kevin Donaldson managed to land the plane, which was fitted with pontoons to land on water, on the Amazon River.

He survived, as did Veronica Bowers' husband, Jim, and their 6-year-old son Cory.

The Association of Baptists for World Evangelism says the plane had filed a proper flight plan and was following accepted procedures when it was shot down.

Doubts

On the videotape, the US commander of the surveillance aircraft is heard saying the missionary plane is not acting like a drug smuggling flight.

"It doesn't match the profile. He is flying too high," he said.

When the shooting down was authorised by the Peruvians, the American pilot expressed concern: "But he is not taking evasive action."

"What?" was the Peruvian pilot's reply.

After the plane is hit, the American asked: "Are you sure is 'bandito'? Are you sure?"

Missionary pilot Kevin Donaldson can he heard screaming on the radio frequency: "They're killing me! they're killing us!"

Co-operation

The US developed joint drug interdiction procedures with both Peru and Colombia in the 1990s.

The Bush administration suspended intelligence co-operation with both countries after the missionaries' plane was shot down.

Neither country has the radar capability to continue anti-drug surveillance on its own.

General Kisic said he hoped drug interdiction flights would resume after safeguards are improved.

"For us it is very important that the programme resumes. At this time, we are aware that the skies of the Peruvian jungle are being inundated by narcotics traffickers."