OVIEDO, Fla. -

Fire gutted the Oviedo Diner early Friday morning, but the cause of the blaze is not known.

The Oviedo Diner, located on Geneva Drive near the Oviedo Library, ignited around 1 a.m., but flames flared up from the roof of the restaurant well after firefighters began battling the blaze.

Fire officials, who had not entered the building as of Friday morning over fears of a roof collapse, said the fire may have started in the kitchen.

"There's substantial damage to the inside of the building," Oviedo Fire Chief Lars White said.  "It's not going to open anytime soon.  There's enough damage inside that it's going to be closed for a duration."

Tony Nikollaj, the owner of the diner, which used to be a Dairy Queen, said the back-to-school season was one of his busiest times of the year.

"(The diner) was my life.  I've been here for eight years. I love the people. For eight years, I never got robbed, nobody stole anything from me.  It was like a family-run business, you know," Nikollaj said.

The cause of the fire is under investigation.

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