Swiss authorities said on Monday that a skiing group led by Britain's Prince Charles was to blame for an accident on the slopes here in which one of his close friends was killed and another injured.

But a report issued by the investigating magistrate said that there were no grounds to press charges against the heir to the British throne for the incident, which occured on unmarked slopes at this fashionable resort here on March 10.

"It is clear from our investigation that Prince Charles' group itself set off the fatal avalanche," the report said. "Other causes can be excluded."