The iconic International Book Mine, a holdover from before Gaines Street became a trendy commercial and residential corridor, was destroyed by Thursday afternoon.

Tallahassee Fire Department crews responded to the scene at 672 Gaines St. as the afternoon rush hour heated up. No one was injured although the store was open for business at the time, said TFD spokeswoman Sarah Cooksey.

The cause of the fire is unknown and being investigated. The fire burned for several hours and the building was a total loss.

Owned by Jayson Hayes, the used bookstore remained open on Gaines Street even as its surroundings were transformed into the bustling College Town with student apartments, parking garages, restaurants, specialty shops and salons.

The store was filled from floor to nearly the ceiling with books. Hayes had amassed 100,000 titles, including rare biographies and classics.

"With all the books in there, it's a really heavy fuel load - that's why it's taking so long to get it out," Cooksey said.

Firefighters had to cut open and peel back parts of the aluminum siding of the Quonset hut to extinguish portions of the blaze. Smoke from the fire could be seen and smelled for miles. Firefighters wheeled bicycles out of the neighboring business, University Cycles. The two businesses share a wall. Because of the fire, Gaines and Madison streets were closed for hours.

More about the Book Mine: Gaines Street: Bookendedby development

Kathryn Casello, 20, a third-year student at Florida State, said she and her boyfriend were at his apartment when they got a call about something on fire. They went to find the source of the smoke.

Casello said she was saddened to find it was the Book Mine. She remembers being impressed by all its old and obscure books. Before she left on a trip to Italy this summer, she bought a book there about the city of Milan.

“The whole entire thing was full of bookcases, all the way to the ceiling," she said. "It was hard to walk around, the whole building was just full of really old books."

Michael Heron was working at University Cycles when the blaze started.

"It’s crazy to think about, but it’s more like, how didn’t this already happen?" he said. "It was like a storefront of kindling."

Contact Ryan Dailey at rdailey@tallahassee.com or on Twitter @RT_Dailey.

Contact Ashley White at adwhite@tallahassee.com or on Twitter @AshleyyDi.

Staff writer CD Davidson-Hiers contributed to this report.