HILLSBORO, Ore. -- A restaurant's interior was destroyed by fire early Wednesday morning and three other businesses were damaged by the smoke created, fire officials said.

Two Starbucks employees came to work just before 5 a.m. Wednesday to find the building filled with smoke.

The employees called 911 and reported that the business next door was filled with smoke and the glass was darkened.

Firefighters arrived at 4:52 a.m. to find fire and smoke inside of the Nice Rice restaurant.

Twenty-two firefighters from the Hillsboro Fire Department and Tualatin Valley Fire and Rescue quickly contained the fire to the restaurant.

Three other business suffered smoke damage from the blaze and Starbucks remained closed Wednesday to clean up the damage.

Fire investigators from the Hillsboro Fire Department were still trying to determine the cause of the blaze that started in the kitchen area as of 3:30 p.m. Wednesday.

The building doesn't have sprinklers and the blaze quickly destroyed the interior of the restaurant.

Preliminary estimates put the loss at about $300,000 with no injuries reported.