Rescuers in Italy working to free cave explorer trapped underground

Emergency cervices attend a rescue operation to free Ottavia Piana, an expert spelunker who was trapped while exploring the cave of Bueno Fonteno, near Bergamo, Italy (LaPresse via Spada/AP)

A major rescue operation is under way north-east of the Italian city of Bergamo to free a woman considered an expert spelunker who was trapped while exploring a cave with eight others.

Ottavia Piana is blocked in a deep inside the Bueno Fonteno cave, where the temperatures were ranging from 7-8C in high humidity.