A fire destroyed the Fair Mart Market on Saturday night after flames tore through the store at 14th and D streets, producing thick columns of black smoke that blew north into downtown Modesto.
The store was closed and nobody was inside when the fire started, Modesto Fire Department Battalion Chief Hugo Patino said.
No injuries were reported, although firefighters narrowly missed disaster when they raced out of the store shortly before its burning roof collapsed.
About 7:45 p.m., a fire department company on its way back to the station from a call spotted heavy smoke and flames coming from the small grocery store, Modesto Fire Battalion Chief Rich Sasser said.
The fire was coming from the attic, although it hasn't been determined whether it started there, Patino said.
The cause and origin had not been determined late Saturday night, Patino said.
The heavy flames and nearby homes prompted firefighters to call for a second alarm, bringing more fire crews as about 50 people, either nearby residents or passers-by, watched them fight the blaze.
Bertha Andrade, a member of a Community Emergency Response Team of Spanish-speaking Latinos trained to assist fire and police officials, was driving along D Street when she saw flames and smoke coming from inside the store.
Andrade is trained to stop and help when she spots an emergency, so she parked her car and pulled on a safety hat, plastic goggles and green vest identifying her CERT credentials.
"I saw the the windows in the store explode from intense heat," Andrade said. "I didn't know what to think."
She helped keep the crowd from getting too close to the firefighters and the smoke rolling down the street. Modesto police closed the intersection and cut off traffic at 14th and E streets and 15th and D streets.
Abraham Aguayo, 35, was working with his sister inside their family's taco truck business, Tacos Vallarta, when they heard a loud explosion.
"We thought somebody had crashed," Aguayo said in Spanish. "We ran out and the store was engulfed in flames. The explosion was the windows bursting."
Aguayo and many others stood across the street watching with video and digital cameras as the top of the west end of the building fell to the sidewalk along 14th Street.
Sasser said firefighters began with an interior attack, but signs of structure collapse changed their strategy.
He said the smoke changed color from light brown to black and increased in density.
"When you see it get really thick and it starts moving fast, you're going to have a flashover situation," Sasser said. "That's when the entire building is burning from top to bottom."
Sasser said none of the nearby homes was evacuated because firefighters had created a strong perimeter of hoses around the building and on top from a firetruck equipped with a 105-foot aerial ladder.
Fire crews had the fire under control by 10 p.m. and were extinguishing smoldering spot fires throughout the building. Patino said "we're going to be out here for a long time putting out this fire."
Bee staff writer Rosalio Ahumada can be reached at firstname.lastname@example.org or 578-2394.