San Diego emergency crews rescued a man over the weekend who had been stranded in a Rose Canyon-area ravine for more than two days after falling and injuring himself, authorities said Monday. The man tumbled down a steep embankment near the intersection of Interstate 5 and state Route 52 in University City on Friday morning while trying to navigate heavy brush, according to the San Diego Fire-Rescue Department. The reason for the fall were not clear. His cries for help were heard Sunday night by a passerby, who called for emergency assistance around 9 p.m., the agency said. Firefighters used chainsaws and other tools to cut through dense vegetation and employed ladders to cross ravines and descend drop-offs, officials said. After about 90 minutes, they reached the man, assessed his condition and airlifted him to a hospital, the department said. The extent of his injuries and his current condition was not immediately known.