BERKELEY -- The world-famous Chez Panisse restaurant was damaged by a fire early Friday morning, but a sprinkler in a downstairs dining room may have saved the building, fire officials said.

As the sun rose over the Berkeley hills, a tearful Alice Waters stood in front of the iconic Berkeley institution that she cofounded in 1971, recalling a fire that started more than 30 years ago, as she cooked in the kitchen.

"It brings up a lot of emotional sadness for me," a barely audible Waters said to rows of news cameras and microphones. "It reminded me of the first time when the fire took out a wall between the kitchen and the dining room. I'm just glad nobody was in the building."

The restaurant, where U.S. presidents have dined, will be closed at least through March 23. Fire officials have all but ruled out arson and are focusing their investigation on some electrical equipment under the front porch of the Shattuck Avenue building.

After touring the darkened restaurant with fire officials early Friday morning, the stress of the event was evident on Waters' face which morphed from a grimace to a smile and back to the countenance of someone trying very hard to keep herself together. As she exited the building and crossed the street to talk with reporters, a fire official accompanied her, and she hugged her longtime pastry chef Mary JoThoresen.

A note posted on the Chez Panisse website Friday said restaurant staff would be calling diners to cancel reservations through March 23. It said the restaurant will not take any new reservations until after March 11.

No one was injured in the blaze, which was reported just after 3 a.m. The fire was under control by about 4:30 a.m.

Damage was heavy in the front porch area, near where the fire was thought to have started. Flames spread inside the building, to a downstairs dining area, but a sprinkler there controlled the blaze as firefighters worked from the inside, likely saving the building, said Berkeley fire department spokesman Avery Webb.

Friday morning Waters already had some new ideas for fixing the charred downstairs portion of her restaurant.

"The first thought I had is maybe we should extend the dining room out," Waters said.

The fire initially was being treated as suspicious in nature because it started under the porch, which is "unusual," Webb said. But investigators then focused on some electrical equipment under the porch as a possible cause.

"So far there is no obvious evidence of arson," Webb said late Friday.

As for reopening, both Waters and Webb said the real issue aside from the fire will be smoke damage to the entire restaurant.

"It's hard to say what they'll allow us to do," Waters said. "It's always smoky in the restaurant anyway. I guess we'll just have to burn more rosemary."

She said it was a "miracle" that there appeared to be no damage to the structural beams that hold up the building.

Foodies, former chefs and contemporaries of the Berkeley food scene piled Waters with praise for her years of cooking and wished her restaurant a speedy recovery.

"Fire is not new to Chez Panisse, so they are very lucky," said Gayle Pirie, co-owner and chef of the Foreign Cinema restaurant in San Francisco and a Chez Panisse cook from 1994 to 1997. "They will probably have a swift turnaround and it will be stronger and more beautiful than before. And the Obamas will probably come out and reinaugurate the restaurant when it's rebuilt."

Alice Medrich, a contemporary of Waters who ran the Cocolat truffle shop down the street from Chez Panisse from 1976 to 1990, said "this too shall pass."

"But the idea of it not being there is an emotional thing," Medrich said, "especially in this neighborhood. Losing that beloved old building would have been a huge loss. But thank heavens no one was hurt and the building was saved."

Webb said the city's health department will have to inspect the building before it reopens. He estimated the damage at $150,000 to $200,000.

Doug Oakley covers Berkeley. Contact him at 510-843-1408. Follow him at Twitter.com/douglasoakley.

Staff writer Daniel M. Jimenez contributed to this report.