MILAN — A major rescue operation was underway Monday in a cave northeast of the Italian city of Bergamo to free a woman who was injured in a fall and became trapped while exploring with eight other people.

Ottavia Piana, 32, remained blocked deep inside the Bueno Fonteno cave, where the temperatures were ranging from 44-46 degrees Fahrenheit in high humidity.

Piana, considered an expert cave explorer, was injured after falling some 16 feet Saturday evening during an expedition to map a half a mile of an uncharted branch of the cave, but rescuers said she is alert and responsive.

She suffered multiple traumas, including to the face, ribs and knee, rescuers said. Members of her team reported her missing after reaching the surface Saturday evening, and rescuers reached her late Sunday. They are using small explosives in an attempt to breach the last 100 yards to reach her.

A spokesman for rescue operation, Mauro Guiducci, said it was impossible to foresee how long it would take to free Piana.

– The Associated Press