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By Marty Graham
SAN DIEGO, May 14 (Reuters) - Wildfires roared out of control in Southern California, forcing authorities in San Diego county on Wednesday to order thousands of people to abandon their homes, including students at a state university, though no major injuries were reported.
Television images showed several homes in flames, with thick black smoke filling the sky and drifting over the Pacific Ocean, as California entered the height of wildfire season in the midst of one of the state's worst droughts on record.
One fire, which erupted shortly before 11 a.m. in Carlsbad, some 25 miles (40 km) north of San Diego, quickly became the most pressing battle for crews fighting flames across the region amid soaring temperatures and hot Santa Ana winds.
In Carlsbad at least eight residences, one apartment building, and two businesses burned to the ground. A state university was evacuated in nearby San Marcos amid other evacuation notices.
Officials told a news conference that nine fires had burned more than 9,000 acres in the county by late Wednesday.
Another fire, called the Tomahawk, broke out on the Camp Pendleton Marine Base north of San Diego and had charred roughly 6,000 acres (2,428 hectares) by Wednesday evening, prompting evacuation of military housing and a naval weapons station.
Fire officials fear the drought could be provide the tinder for a particularly dangerous year for wildfires in the state.
Thousands of homes and businesses and cell phones in and around Carlsbad received directives to evacuate, according to the city authorities, and emergency shelters were set up at schools and community centers.
Authorities were growing increasingly concerned about a fresh blaze that broke out in the late afternoon in San Marcos, where thousands of residents and students at a California State University campus were ordered to leave.
"The fire was right above campus. I could see it reaching over part of the hill, this really dark smoke. It was almost like an explosion," said 19-year-old Grant Rapoza, who was in his dorm room when the school issued evacuation notices.
California Governor Jerry Brown on Wednesday declared a state of emergency to free up resources, saying he had secured a grant from the Federal Emergency Management Agency to help aid local firefighting efforts.
San Diego Gas and Electric reported that more than 2,300 customers in the Carlsbad area were without electricity.
The Legoland amusement park was also evacuated, spokeswoman Julie Estrada said, mostly because of power outages.
Southern California Edison said 13 employees were also evacuated from the largely shuttered San Onofre Nuclear Generating Station some 20 miles (32 km) north of Carlsbad as a precaution, but were allowed to return later in the afternoon.
San Diego Unified School district and other districts canceled Thursday classes.
"It's right in the middle of the city," California Department of Forestry and Fire Protection spokesman Daniel Berlant said of the so-called Poinsettia Fire, which had blackened more than 100 acres (40 hectares) by mid-afternoon.
He said Cal Fire was assisting the Carlsbad Fire Department in fighting the flames and had deployed water-dropping aircraft.
The new fires erupted just hours after crews aided by diminished overnight winds, made substantial headway against the so-called Bernardo Fire, which had forced thousands to flee their homes in and around San Diego for several hours in the afternoon and evening on Tuesday.
By daybreak on Wednesday, firefighters managed to establish containment lines around 25 percent of the Bernardo Fire's perimeter, with all evacuation orders lifted and area schools reopened, according to fire officials.
Since erupting late on Tuesday morning, the Bernardo fire has scorched more than 1,500 acres (607 hectares), and officials said dangerous conditions persist.
"Tonight, like last night, we expect the winds to calm down," said Dianne Jacob, San Diego County Supervisor. (Reporting by Marty Graham, Steve Gorman and Dan Whitcomb; Writing by Dan Whitcomb and Eric M. Johnson; Editing by Edith Honan, Ken Wills and Simon Cameron-Moore)