A fire gutted a one-story commercial building in downtown Los Angeles Wednesday, but no one was hurt.

Crews were called about 5 a.m. to the 1300 block of South Margo Street and rolled up to a one-story building with smoke showing, according to the Los Angeles Fire Department.

Firefighters encountered heavy fire, fueled by "densely stored clothing,'' along with pallets and cardboard, inside the building, with the bulk of the fire about 40 feet inside, the LAFD reported.

Crews had trouble accessing the flames because of the amount of storage inside the building, the LAFD reported. More than 100 firefighters were assigned to the scene.

Based on conditions, firefighters took up defensive positions -- battling the blaze from the exterior -- after being pulled off the roof and out of the building, the LAFD reported.

Firefighters gained the upper hand on the fire within a couple of hours. The fire was declared out by about 7:30 a.m., said Brian Humphrey of the LAFD.

The 25-foot-by-150-foot building was "filled with densely stored clothing,'' Humphrey said.

"Though permeated with heavy smoke, firefighters prevented all but minimal fire from extending into an adjoining one-story building -- (the) same business but facing Olive Street -- connected by an interior doorway," Humphrey said.

Some firefighters were released from the scene, while others remained at the location dousing hot spots. The cause of the fire was under investigation.