Stock image. Photograph by Richard Schneider

New Zealand wingsuit flyer Dan Vicary and French wingsuit cameraman Ludo Woerth have been killed in an accident in the Swiss Alps, with a third flyer seriously injured.

The men jumped from a helicopter over Lötschental on Saturday, but for currently unknown reasons all three men crashed to the ground near Sengg.

Vicary, 33, and the Woerth, 34, were pronounced dead at the scene of their crash landing near Sengg, with the third man evacuated by helicopter to a nearby hospital.

A message posted on the World Wingsuit League (WWL) Facebook page said:

We are shocked and saddened to hear the news about the fatal wingsuit accident of Ludo Woerth and Dan Vicary. We want to express our deepest condolences for their families, friends and loved ones during these difficult times.

Our thoughts and prayers are also with the third jumper. Out of respect to everyone involved in this horrible tragedy, we will not release any other information at this time.

Wingsuit flying is an extreme sport where participants wear “birdman” suits and jump from cliffs or aircraft and glide with impressive accuracy while travelling at speeds of around 150mph, before parachuting t the ground.