He said investigators had not found an explosive device at the scene.
Officials originally believed the explosion was caused by a auto crashing into the building, but Orange County Sheriff's Department spokeswoman Carrie Braun said no vehicle was involved and the department was investigating how the explosion occurred. The person who died was inside the building at the time of the blast, officials said.
The FBI is responding to the scene, a law enforcement official told CBS News senior investigative producer Pat Milton.
Orange County Sheriff's Cmdr. McWilliams says one woman had skin peeling on her arm.
Dutch researchers uncover dirty jokes in Anne Frank's diary
He edited and published her writings in hiding after the war, making Anne Frank one of the world's most famous Holocaust victims. The house where the Franks hid was turned into a museum that is one of Amsterdam's most popular tourist attractions.
The blast involved a building under renovation but the cause was not immediately known, Fennessy said. There were early reports that a auto had crashed into the building, but that turned out not to be the case. The cause of the blast is being investigated. The injured were taken to a hospital. No children were hurt, officials said. They were being reunited with parents at a nearby store parking lot.
"The survivors' injuries were consistent with an explosion, but not necessarily consistent with a bomb". Officials said the structure, which fire officials described as a medical office building, appeared to be under construction.
Although the cause of the blast was still unknown, Bommarito told reporters around 3:30 p.m. that there was "no immediate hazard" to the community.
Treasury yields surge pushes Wall Street lower
The Dow Jones industrial average fell 193 points to close at 24,706.41, with Home Depot among the biggest contributors of losses. Stocks struggled to a mixed finish on Wall Street as weakness in smaller-company stocks offset gains in large companies.
White House calls deaths in Gaza 'propaganda' by Hamas
The Palestinian Health Ministry said more than 1,600 had suffered injuries, and that numerous dead had not yet been identified. Israel said some 40,000 Palestinians had taken part in " violent riots " at 13 locations along the Gaza Strip security fence.
3-year-old pees during marriage proposal
Anter said they weren't surprised since they've been working hard on potty training Owen this past month. Przytula stopped his girlfriend in front of a fountain and romantically dropped down to one knee.
China's Didi Chuxing to Test Self-Driving Cars in California
Despite the recent steps it's made, analysts predict we won't be seeing cars with fruit logos driving around until at least 2020. That gives it the second-largest fleet in the U.S. , ahead of Waymo's 51 cars, but still well behind GM Cruise, which boasts 104.