At least 13 people have died in a violent wave of wildfires in southern California that have burned around 500 homes and forced tens of thousands of people to flee, officials said. Eleven people were confirmed to have died in fire-related incidents around the city of San Diego, south of Los Angeles, while two others succumbed as a result of a fire in San Bernardino County, east of here. "We have 11 known fatalities as a result of the fire so far," said San Diego County Sheriff's Department spokeswoman Adriana Uribe told AFP. San Diego County Sheriff William Kolender said several other deaths were being investigated as possibly fire-related. At least two of the dead were trapped in a burning car as they tried to escape the San Diego fire, officials said. And in another inferno in San Bernardino, about 80 kilometers (50 miles) east of Los Angeles, two elderly people died of heart attacks as the fire closed in on their homes, officials in the area said. Kolender said parts of San Diego, a city of 1.2 million, were being evacuated under threat from two separate fires, which have burned 37,200 hectares (93,000 acres) and destroyed 136 homes. The fire that has been raging east of Los Angeles since Tuesday merged with another blaze, chewing up 20,000 hectares (50,000 acres) of land and destroying at least 360 homes, fire officials said. A further 27,400 homes are threatened by the giant blaze creeping into the communities including Rancho Cucamonga, Fontana and Upland in the San Bernardino mountain foothills. Kolender told residents to "not hesitate to pack your belongings and leave" if the fire comes their way and pay attention to broadcasts from local authorities. "This is a very serious situation. Pay attention to what you hear from law enforcement, pay attention to your television set," he said. **PHOTO CAPTION*** Firefighters pour water onto burning homes as they fight a wildfire that is sweeping through San Diego Sunday, Oct. 26, 2003. (AP Photo/Lenny Ignelzi)