Three people were killed and eight injured on Friday when scaffolding collapsed off a 19-storey building under construction in the western Swiss city of Lausanne, according to police officials.

The scaffolding collapsed shortly before 9:30 am local time according to a witness.

The scaffolding structure on one side of the 60-metre (200-foot) tower collapsed, sending construction workers tumbling to the earth.

According to regional authorities, the tragedy near Prilly, on the outskirts of Lausanne, killed three construction workers and injured over a dozen others who are still receiving treatment in the hospital.

Police spokesman Jean-Christophe Sauterel said the cause of the accident remained unclear.