The day after five German mountain climbers fell 100 metres to their deaths in the Swiss Alps, police say they still do not know what caused the accident.
The climbers - who included on adolescent - were not tied together with a cord which is one reason why a group of climbers may have fallen together.
Swiss police have been speculating as to the causes but say it is still under investigation.
(SOUNDBITE) (French) VALAIS POLICE SPOKESMAN JEAN-MARIE BORNET:
"Possibly it's an avalanche. It is a corniche? Is it falling rocks? We're trying to check this. The fact is that five people have died."
There was one survivor from the expedition, who did not finish the climb and was able to raise the alarm.
Simon Hanna, Reuters.