A trip of a lifetime for three couples ended in tragedy this week after their seaplane plunged into the ocean off Rottnest Island, sending shockwaves around the world.

A light aircraft crashed near Rottnest Island off the Western Australian city of Perth killing two tourists from Switzerland and Denmark and the pilot, authorities said on Wednesday.

At least three people were killed after a small seaplane crashed during take-off from an Australian tourist island. The Cessna 208 Caravan plane crashed on Tuesday while leaving Rottnest Island, which is famous for its friendly marsupials called quokkas.