Rescue workers in Chile are searching a central mountainous area for an air ambulance that crashed while carrying six people, authorities say. The aircraft was transporting a patient when it lost contact with authorities near Cerro El Roble mountain in the Curacavi area, outside Santiago. "We still haven't reached one of the key points... we are facing adverse conditions," said Bastian Alarcon Atenas, the Presidential Delegate of Melipilla, to the press. IMAGES AND SOUNDBITES