The bodies of the seven victims of Tuesday's helicopter crash will be returned to India as early as Friday. Police in canton Valais said they were working with the Indian embassy to make the necessary arrangements.

A spokesman said flights were being arranged, and that the victims' bodies would be flown out on Friday or Saturday.

Four of the people injured, three of whom are Indian tourists, are still in hospital, but their lives are not in danger.

Investigators into the collision of the two helicopters - which killed seven Indian tourists and a Swiss pilot - still do not know what caused the accident.

The owner of Air-Glaciers and operator of the two helicopters, Bruno Bagnoud, said he believed it was possible that the dead pilot was blinded by the setting sun and could not avoid an accident. But the Swiss Office for Aircraft Accident Investigations has ruled out pilot error.

The office said on Wednesday that preliminary investigations were still underway, and that the cause of the accident was still unclear. As many eyewitnesses as possible are being questioned.

The accident was the worst helicopter crash Switzerland has ever seen.

The collision occurred as the two helicopters, a Bell Jet Ranger and an Alouette III, both belonging to the Air-Glaciers company, were coming in to land on the football field in Beuson, a village near the town of Sion in canton Valais.

The aircraft had just completed a five-minute sightseeing tour above the surrounding Alps for the Indian tourists. The crash was witnesses by about 60 other Indians, who had already had their turn.

Eyewitnesses said the helicopters moved very close to each other as they were hovering about 15 metres above the field. They said they fell to the ground after their rotor blades touched.

All six passengers and the Swiss pilot on board the Bell Jet Ranger died. One tourist on board the Alouette was killed in the crash, while the other three passengers and the pilot escaped with injuries.

The tourists were part of a group of around 150 Indians who were on the last day of a holiday to Germany and Switzerland. A group of around 60 of them were waiting at the football field for their sightseeing trips when the crash happened.

The authorities have rejected claims from eyewitnesses that help was too slow in arriving.

This was the second fatal accident involving Air Glaciers this month, after a pilot died in canton Vaud on September 5.

swissinfo with agencies

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