A runaway dog spent two days in a dark Caltrain tunnel in San Francisco before he was rescued, San Francisco Animal Care and Control said Tuesday. However, on the second day, a train operator saw Roo move, according to Animal Care and Control. Animal Care and Control officers went into the tunnel with Caltrain staff and found Roo "scared" and "terrified" but not injured. "He was terrified at first then was thrilled to be rescued," Animal Care and Control said. Animal Care and Control said Roo was recently adopted and took off after getting spooked.