Rescue workers in the flood-ravaged village of Gondo in canton Valais are still trying to reach a woman, who has been trapped by mudslides since Saturday. Torrential rain caused devastation across much of the canton over the weekend.
Police said on Tuesday that rescuers were digging a tunnel through the rubble of a building to try and reach the woman. Soldiers and rescuers with sniffer dogs were alerted to the woman's location after they heard knocking and cries.
A police spokesman in Sion said rescuers were advancing slowly, using saws, shovels and their hands to get to the woman.
"We have to be very careful because a wrong move can lead to a new collapse and could even kill the woman," he said. "We are using flash lights and the dogs are constantly trying to locate her."
The four storey building included offices and homes, and was destroyed after a mudslide wiped out a third of the village on Saturday.
Eleven people are still unaccounted for in Gondo, following the discovery of a woman's body on Monday. One other person is missing in another part of Valais.
So far three bodies have been found across the canton. The latest discovery was of a 70-year-old woman found in the river Rhone near Dorenaz, some 80 kilometres from where her house was wrecked by another mudslide.
Valais remains on a state of high alert, although the rains had eased by Monday. Several towns remain cut off, including the mountain resort of Zermatt. "We expect the links to Zermatt to be restored in two or three days," a tourism official told swissinfo.
Other parts of Switzerland have also been hit by heavy rains. The town of Locarno, in Italian-speaking canton Ticino, is partly under water after Lake Maggiore burst its banks.
The Piazza Grande, in the centre of Locarno, has been flooded, and the emergency services are on a state of high alert.
The level of the lake has reached a record high, rising beyond levels reached in 1993. Meteorologists say the rains that have swept the area are expected to ease on Tuesday.
swissinfo with agencies