The San Bruno pipeline explosion occurred at 6:11 pm PDT on September 9, 2010, in San Bruno, California, when a 30-inch (76 cm) diameter steel natural gas pipeline owned by Pacific Gas & Electric exploded into flames in the Crestmoor residential neighborhood 2 miles (3.2 km) west of San Francisco International Airport near Skyline Boulevard and San Bruno Avenue. The loud roar and shaking led some residents of the area, first responders, and news media to initially believe that it was an earthquake or that a large airplane had crashed. It took crews nearly an hour to determine it was a gas pipeline explosion. As of September 29, 2010, the death toll was eight people. The United States Geological Survey registered the explosion and resulting shock wave as a magnitude 1.1 earthquake. Eyewitnesses reported the initial blast "shot a fireball more than 1,000 feet (300 m) in the air".