SIERRA MADRE, California (CNN) -- A 400-acre wildfire raging through dry brush and shrubs in Southern California was about 30 percent contained by Sunday afternoon, an official said.
An airplane drops flame retardant on a slope Sunday in Sierra Madre, California.
"Winds are very favorable right now, they're very light, humidity was up today at about 20 percent," said Marc Peebles, of the Southern California Incident Management team, which has assumed control of fighting the blaze in Sierra Madre's mountains.
"Hopefully, the weather's going to hold," Peebles said at a Sunday afternoon news conference.
Authorities ordered about 1,000 people to flee their homes Sunday, and Peebles said all Sierra Madre schools would be closed Monday.
The fire is "running way out in the Angeles National Forest -- that's where we're having a problem engaging the fire safely," Tim Davis, of U.S. National Forestry Service, said at the news conference. Watch firefighters battle the blaze »
Among those forced to leave Sunday was a wedding party of about 50 people who woke up the morning after the nuptials to find search-and-rescue officials telling them to evacuate.
"It was sort of shocking. I didn't think that we were going to have to be airlifted out," the bride, Julie Grady, told CNN.
One firefighter battling the blaze had a minor injury to his knee, and was treated at a hospital and released, Los Angeles County fire officials said. Otherwise, there have been no reports of injuries.
Peebles said he hoped firefighters could fully contain the fire in four days to a week, depending on weather conditions.
No homes have been destroyed, though some are threatened as the blazes spread, causing the mandatory evacuation orders for about 400 houses, fire officials said. However, Davis said that "most of the risks [to the structures] are being removed."
City Manager Elaine Aguilar said one gardening shed was destroyed.
"We don't know what started the fire. But we do know that it wasn't some natural cause such as lightning or something like that. We do know that it was man-made," she told "CNN Sunday Morning."
About 500 firefighters were working to battle the blaze, Davis said. City spokeswoman Elisa Weaver said earlier that the firefighters were receiving air support from two helicopters and three water tankers. Aircraft would operate until dark, Peebles said. Watch the march of a wind-driven wildfire »
Separately, in San Diego, a 50-acre fire burned in what fire officials described as open space. Officials said the fire was not threatening homes and there were no calls for evacuations.
The blaze in Sierra Madre began Saturday in an area that has not seen fires in more than 30 years, which means it has a great deal of kindling -- such as dry brush and shrubs -- to fuel the flames, Aguilar told CNN. And the terrain is rugged, hampering firefighters' efforts. The hot weather -- with temperatures in the mid-90s by midday -- added to the challenge.
A shelter was opened for those forced from their homes, fire officials said. Aguilar told CNN about 30 to 40 people spent the night at one shelter, a local senior center.
Aguilar called on residents to heed the warnings of public safety personnel. Some roads "are very narrow" and must remain clear for safety personnel to make it into the area, she said.
Sierra Madre is in Los Angeles County, about 13 miles northeast of downtown Los Angeles.
For the wedding party, the situation came as a surprise.
The groom, Ken Grady, told CNN, "We were going to do it Labor Day weekend when the fire danger is high. So we thought, 'April, no problem.' Obviously, fire danger is high all the time in Southern California." Watch the couple talk about their eventful weekend »
After the wedding Saturday afternoon, "We did smell some smoke and were informed of the fire last night," Bride Julie Grady told CNN on Sunday. She added that the group "didn't realize, I guess, how bad the danger was until this morning, when search and rescue came up to the camp and started evacuating us."
Ken Grady said the officials "got a little nervous energy going around the whole group," but all reached safety. "It was exciting -- and a little nerve-wracking," he said.
Mary Jo Sokolowski, Julie Grady's sister, called it "quite an adventure."
As for the happy couple, she said, "They're doing good, and it definitely made it quite, you know, a great memory, actually." E-mail to a friend
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