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Investigators say they have determined what caused a major forest fire in canton Valais last year.
It took weeks to bring the blaze under control, which started this time last year. It destroyed 135 hectares of woodland.
After ruling out lightning and sunlight as the cause, the focus turned to a powerline.
A nearby electrical substation suffered an outage just before the outbreak. This was caused by a broken cable.
After examining the line, investigators say it had been hit by several rounds from a rifle. The shots were fired from the Flesche area.
Cantonal police are now asking for any information about the incident.