NORWALK - Some Norwalk residents say they were surprised to discover that the shaking they felt earlier today was caused by an earthquake. According to the U.S. Geological Survey, the 5.8-magnitude earthquake struck shortly before 2 p.m. in rural Virginia. The shockwaves were felt as far north as Toronto. One local woman said she felt her car shaking and assumed crews were working on pipes under the street. She says she was on New Canaan Avenue near Route 7 when she felt the tremors. "I kept thinking, 'It can't be an earthquake,'" she said. "I kept thinking, 'There's something underground. Maybe there's work being done.'" Shopkeepers in the city say they found no signs of damage.Quake rocks Washington area, felt in Connecticut