Firefighters are at the scene a four-alarm fire at 1050 University Drive at Santa Cruz Avenue in downtown Menlo Park, across the street from Fremont Park.
The building where the fire occurred has several businesses, including Peet's Coffee & Tea and the Calla boutique. The fire appeared contained by mid-morning.
Chief Harold Schapelhouman of the Menlo Park Fire Protection District said the fire may have originated in the walls and floor of the offices on the second floor. The investigation is still in early stages, but the slow-burning fire could have crept up behind the drywall from the coffee shop or somewhere else in the building.
"It was going all night long," he said. "It's a very unique fire. It's all around you and you can't see it."
Chain saws and axes were used to break through the walls and floor to get to the source of the flames, he said. Firefighters worked in full gear in shifts of 15 to 30 minutes, depending on the intensity of the work, Chief Schapelhouman said.
Firefighters hacked out the roof to vent it. In what was left of the mail-services office, the joists and framing were blackened and charred, while drywall seemed none the worse for wear, at least to a reporter taken on a tour of the damage by Chief Schapelhouman.
"It's been a smoking, hot, difficult problem fire," he said.
By mid-morning, there were 47 firefighters and seven officers on the scene, 11 engines, three trucks and a breathing support unit. Firefighters from Belmont, Woodside and Palo Alto were among the companies represented.
One firefighter suffered a shoulder separation as he was cutting away boards to get to the source of the fire.
Peet's was evacuated and articles of clothing, many damaged by smoke, were removed from Calla. The clothing will probably be donated as it's too damaged to be sold, Calla owner Phil Bachler said.
Calla suffered extensive water damage. Chief Schapelhouman told a Peet's store manager that the use permits for the building will be "pulled." Peet's also has water damage, but not to the extent of Calla.
Calla may be closed for months, said Mr. Bachler, who bought the store seven months ago with his wife Tiger. A remodel was to have begun this week, he said. He is insured, he said.
"That was a clothing store. Now it's a catch basin for water," Chief Schapelhouman said, looking down through the floorboards into the standing water in the boutique as firefighters chopped away at the walls and floors of the second-story office. "We're doing a remodel, only we don't want to be doing it."
Firefighters bagged what clothes they could, Chief Schapelhouman said. "We don't enjoy doing damage, but we've got to find the fire."
Police had diverted traffic around the scene, but that ended about mid-day.