A fire burned through a row of one-story retail businesses on Monday in the heart of the North Hollywood Arts District, causing severe damage to five shops.

The blaze originated at Tokyo Delve’s Sushi Bar in the 5200 block of Lankershim Boulevard and was first reported around 5:30 a.m. It was deemed a structural fire after roaring through the property’s attic and causing a significant chunk of the roof to cave in. Billowing smoke could be seen from as far as the Warner Center in Woodland Hills.

More than 100 firefighters and five ladder trucks from Los Angeles Fire Department responded to the emergency calls. It took crews more than two hours to douse the flames. Before they did, the fire and smoke spread to four adjacent storefronts, including ice cream shop Chill Rollz, Greenhouse Juice Bar, District Pub NoHo and Joe Coffee, which suffered varying degrees of damage.

Firefighters blocked off a section of Lankershim Boulevard between Magnolia Boulevard and Weddington Street through Tuesday morning in order to finish mop-up work.

No one was hurt by the blaze, but one business owner was transported to a hospital with a head injury sustained during a physical altercation with another business owner over the cause of the fire. One accused the other of intentionally starting the fire and causing the extensive damages suffered by his shop and others, leading to a fistfight.

The combatants have not been personally identified but both were detained by the Los Angeles Police Department on battery charges. Another person at the scene was arrested for a misdemeanor warrant. No arrests were made in direct relation to the fire.

LAFD arson investigators and federal agents from the Bureau of Alcohol, Tobacco, and Firearms are leading a probe into the fire’s origin, as is protocol for all major emergency fires. They have not yet made a determination.