Brigadier-General Daniel Leaf of the United States Air Force, said that there had in fact been two convoys and he admitted there may have been civilian casualties at both locations. The following is a detailed account of his briefing:

According to Gen Leaf, a number of Nato planes had been engaged with Serbian forces in the western area of Kosovo before approaching the convoys.

Video of the first convoy bombing taken by the F-16

Their brief was to find and identify targets in the western half of Kosovo.

The first convoy target, on a road north-west of the town of Djakovica, was attacked by Nato planes at approximately 1030 GMT.

Serbian TV footage reportedly of the attack on the convoy

The attack involved three F-16 air missions, Bear 41, and later Bear 21 and Bear 31.

The Bear 21 F-16 pilot had identified the convoy as containing vehicles that appeared to be the perpetrators of house-burning in Djakovica.

He had observed individuals fleeing from a house which had been set on fire by members of the convoy in that area. Further vehicles had joined the convoy prior to the air attack.

Second convoy spotted

The second incident, on a major road south-east of Djakovica going towards Prizren, appeared to involve a large convoy led by military vehicles.

From the pilots' altitude, both convoys appeared to be military

It was spotted by another F-16 sweeping the area as the Nato planes to the north-east of Djakovica ended their bombing.

The F-16 bomber, Bear 41, which had been involved in the earlier bombing, joined two Jaguar aircraft, Saab 51 and Saab 52, in an attack on the second convoy.

Gen Leaf, based at a US air base in Italy, said that after exhaustive reviews of the mission tapes, and interviews with the pilots involved, he was satisfied that this target appeared at first to be military in nature.

From the 15,000ft altitude of the F-16s, the vehicles were taken to be Serbian forces because:

• they appeared to contain more than 20 vehicles
  
• the vehicles were uniform in shape and colour
  
• the vehicles maintained a uniform distance and space
  
• they were travelling at a relatively fast speed.

Air attacks against the convoy were suspended when doubts were raised about the nature of the convoy.

Identification reassessed

A reconnaissance plane called in to reassess the nature of the convoy identified some military vehicles by binocular, but said some of the vehicles were civilian.

The second attack was to the south-east of the town

Gen Leaf admitted that from the videos taken by the F-16s, some of the vehicles in the second convoy could have been identified as civilian tractors.

The rear of the convoy, which appeared to be transporting fuel, may have contained non-militay vehicles.

Gen Leaf said it was a complicated scenario and all the exact details might never be known.

He said the second convoy may have contained both Serbian military vehicles and Kosovo-Albanian vehicles, possibly being used as shields.

It was also suggested that Serbian forces operating in the area might have been responsible for some of the deaths at the second location, perhaps using machine guns on the refugees.

"We simply cannot verify which types of targets were struck by whom," said Brigadier Leaf.

"After Nato attacked the front vehicles, Serbian planes may have attacked the rear vehicles," he added.

Tape recording controversy

The Pentagon has confirmed that a voice recording of the Nato pilot believed to have bombed the convoy, released on Thursday, was not related to the incident.

Nato spokesman Jamie Shea: "Nato would never knowingly mislead any journalist"

Asked about the audio tape confusion, the UK Defence Secretary George Robertson and Nato spokesman Jamie Shea both said some confusion was inevitable in times of conflict.

"I think it's been a confusing incident, regrettably," Jamie Shea told BBC radio.

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