Fire destroyed 12 unoccupied units in a detached building at the Senator Inn & Spa in Augusta early Friday morning.

State Fire Marshal Rich McCarthy said his office got a call around 12:30 a.m.

“At this point, we see nothing suspicious,” he said. “It looks like the fire started in the ceiling section in a concealed space.”

The fire was ruled accidental Friday afternoon.

The units, which are single-story motel-type rooms, are behind the pool at the inn on Western Avenue. They are seasonal and are typically only rented June through September, hotel General Manager Kaitlyn Martin said.

The main hotel, restaurant, pool and spa continue to operate normally and were unaffected by the fire.

“It didn’t cause any damage or concern to the main building or back buildings,” Martin said.

Some of the rooms destroyed by the fire had been reserved for late July when the Ironman returns to the city. Martin said there are other rooms available at the inn to accommodate those guests.

She said the hotel is likely to rebuild the stand-alone units, which are popular with visitors who like drive-up access near the pool.